Consider the proof.

Given: In △ABC, BD ⊥ AC
Prove: the formula for the law of cosines, a2 = b2 + c2 – 2bccos(A)

Triangle A B C is shown. A perpendicular bisector is drawn from point B to point D on side A C. The length of B C is a, the length of D C is b minus x, the length of A D is x, the length of A B is c, and the length of B D is h.




Statement

Reason
1. In △ABC, BD ⊥ AC 1. given
2. In △ADB, c2 = x2 + h2 2. Pythagorean thm.
3. In △BDC, a2 = (b – x)2 + h2 3. Pythagorean thm.
4. a2 = b2 – 2bx + x2 + h2 4. prop. of multiplication
5. a2 = b2 – 2bx + c2 5. substitution
6. In △ADB, cos(A) = StartFraction x Over c EndFraction 6. def. cosine
7. ccos(A) = x 7. mult. prop. of equality
8. a2 = b2 – 2bccos(A) + c2 8. ?
9. a2 = b2 + c2 – 2bccos(A) 9. commutative property
What is the missing reason in Step 8?

Pythagorean theorem
definition of cosine
substitution
properties of multiplication

The incorrect step is ln(x²) = ln(3x/0) because ln(x/y) = lnx - lny and the solutions are x = 0, 3

It is another way to represent the power of numbers, and we say that 'b' is the logarithm of 'c' with base 'a' if and only if 'a' to the power 'b' equals 'c'.

[tex]\rm a^b = c\\log_ac =b[/tex]

The question is incomplete.

The complete question is in the picture, please refer to the attached picture.

We have:

2ln(x) = In(3x) - [In(9) - 2ln(3)]

In(x²) = In(3x) - [In(9) - In(9)]

ln(x²) = ln(3x) - 0

ln(x²) = ln(3x/0)   (incorrect step)

ln(x²) = ln(3x)

x² = 3x  (correct step)

x² - 3x =0

x(x - 3) = 0

x = 0, 3

Thus, the incorrect step is ln(x²) = ln(3x/0) because ln(x/y) = lnx - lny and the solutions are x = 0, 3

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Step-by-step explanation:

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The value of the expression x

4

−8x

3

+18x

2

−8x+2, when x=2+

3

, is:

Medium

Solution

verified

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Correct option is B)

Let f(x)=x

4

−8x

3

+18x

2

−8x+2

Substituting x=2+

3

, we get

f(2+

3

)=(2+

3

)

4

−8(2+

3

)

3

+18(2+

3

)

2

−8(2+

3

)+2

=(2+

3

)

2

((2+

3

)

2

+18)−8(2+

3

)((2+

3

)

2

+1)+2

=(7+4

3

)(4

3

+25)−8(2+

3

)(8+4

3

)+2

=175+48−128−96+2

=1

Hence, option B is correct.

Answer:

$4,000.343

Step-by-step explanation:

Divided the months of the year and caculate the intrest.

Assuming average cost of $55.5, the cost of goods sold by Olympic Enterprises for the June 14 sale is equal to $444.

In Financial accounting, the cost of goods sold for a business firm can be calculated by multiplying the total quantity of goods by an average cost. Mathematically, this is given by:

Cost of goods = quantity × average cost

Note: We would assume an average cost of $55.5.

Substituting the parameters into the formula, we have:

Cost of goods sold = 8 × 55.5

Cost of goods sold  = $444.

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(a)

421₅ = 4×5² + 2×5¹ + 1×5⁰

… = 100 + 10 + 1

… = 111

(b)

11101₂ = 1×2⁴ + 1×2³ + 1×2² + 0×2¹ + 1×2⁰

… = 16 + 8 + 4 + 0 + 1

… = 29

(c)

13T₁₂ = 1×12² + 3×12¹ + 10×12⁰

… = 144 + 36 + 10

… = 190

Answer:

25/36

Step-by-step explanation:

put 2500 over 3600 and you get 2500/3600 but you can simplify to get 25/36 but removing the 0's

Answer:

0.42 dollar per pint

2.36 pints per dollar

THE ANSWER IS -> b. x > 1

hope it helps

thanks

Answer: c. x>0

Step-by-step explanation:

Answer:

D) 8[tex]\frac{1}{2}[/tex]

Step-by-step explanation:
5[tex]\frac{2}{3}[/tex] ÷ [tex]\frac{2}{3}[/tex] = 8[tex]\frac{1}{2}[/tex]

Answer:

angle ACB=45º

Step-by-step explanation:

angle 135º lies on a straight line

a straight line = 180º

thus, angle ACB= 180-135=45º

Answer: $12.96

Given:

1305 bags of carrots purchased

Total cost = $16,910

Step-by-step explanation:

To find the unit cost, divide 16910 by 1305 to find the cost of one bag of carrots:

[tex]\frac{16910}{1305} = 12.96[/tex]  (rounded to nearest hundredth)

Answer:

expression for (g + h)([tex]x\\[/tex]) = [tex]2x[/tex] + [tex]3x^2\\[/tex] and for (g - h)([tex]x[/tex]) = [tex]2x[/tex] - [tex]3x^2[/tex]

value of (g .h)(2) = 24

Step-by-step explanation:

function operations: Functions with overlapping domains can be added, subtracted, multiplied and divided. If f(x) and g(x) are two functions, then for all x in the domain of both functions we can find the sum, difference, product and quotient

given :

g([tex]x[/tex]) = [tex]2x[/tex]

h([tex]x[/tex]) = [tex]3x^2[/tex]

we know that ;

(g + h)([tex]x[/tex]) = g([tex]x[/tex]) + h([tex]x[/tex])

              =  [tex]2x[/tex]  + [tex]3x^2[/tex]

similarly;

(g - h)([tex]x[/tex]) = g([tex]x[/tex]) - h([tex]x[/tex])

             =  [tex]2x[/tex] - [tex]3x^2[/tex]

now,  

(g . h)([tex]x[/tex]) = 2([tex]3x^2\\[/tex])

             = 6[tex]x^2\\[/tex]

for (g .h)(2) = 6([tex]2^2[/tex])

                  = 6 × 4

                  = 24

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Answer:

Step-by-step explanation:

If a = 0, f(a) = f(0) = 0 + 0 + 7 = 7;

If a = 1, f(1) = 3(1^2) + 2(1) + 7 = 12;

and so on.  Normally an 'a' value would be given as part of this problem.

Actually, the value of f(a) is given and is  f(a) = 3a^2+2a+7 for input value a.

The school bus will take 5.34 seconds to travel 95.1 m if the bus is moving 26.8 m/s on flat ground when it begins to accelerate at 4.73 m/s².

Any equation of the form [tex]\rm ax^2+bx+c=0[/tex] where x is variable and a, b, and c are any real numbers where a ≠ 0 is called a quadratic equation.

As we know, the formula for the roots of the quadratic equation is given by:

[tex]\rm x = \dfrac{-b \pm\sqrt{b^2-4ac}}{2a}[/tex]

We have:

A school bus is moving 26.8 m/s on flat ground when it begins to accelerate at 4.73 m/s².

From the second equation of motion:

[tex]\rm s = u + \dfrac{1}{2}at^2[/tex]

We have given:

s = 95.1 m

u = 26.8 m/s

a = 4.73 m/s²

[tex]\rm 95.1 = 26.8 + \dfrac{1}{2}(4.73)t^2[/tex]

The above equation is a quadratic equation:

After simplification:

[tex]\rm \dfrac{4.73}{2}t^2=68.3[/tex]

[tex]\rm t^2=28.879[/tex]

t = 5.373 seconds ≈ 5.34 seconds

Thus, the school bus will take 5.34 seconds to travel 95.1 m if the bus is moving 26.8 m/s on flat ground when it begins to accelerate at 4.73 m/s².

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Answer:

- 1

Step-by-step explanation:

note there is a common difference of 6 between consecutive terms , that is

23 - 29 = 29 - 35 = 35 - 41 = 41 - 47 = - 6

by subtracting 6 from the previous term we get

23 - 6 = 17

17 - 6 = 11

11 - 6 = 5

5 - 6 = - 1

the first negative number in the sequence is - 1

The time it will take the money to reach $8,838.51 is 14years

The formula for calculating compound interest is expressed as:

A = P(1+r)^t

where

P = $6,680

A = $8,838.51?

r = 2% = 0.02

Substitute and calculate the time 't"

8,838.51 = 6680(1+0.02)^t
1.3231 = 1.02^t

t = ln1.3231/ln1.02

t = 14years

Hence the time it will take the money to reach $8,838.51 is 14years

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An equation is formed of two equal expressions. The number of infections in 6 weeks is 456.

An equation is formed when two equal expressions are equated together with the help of an equal sign '='.

The general equation of an exponential function is written as,

y = A(B)ˣ

Since the infection is increasing at a rate of 50%, therefore, the rate of growth will be,

B = 1.50

Substitute any value then we will get,

40 = A(1.50)⁰

A = 40

Thus, the exponential equation of the growth will be,

y = 40(1.50)ˣ

Now, the number of infections in 6 weeks will be,

y = 40(1.50)⁶

y = 455.625 ≈ 456

Hence, the number of infections in 6 weeks is 456.

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When decomposing into prime factors, it is when a number is taken out of its half, third, fifth and seventh, and it is also possible for the same number number.

         [tex]\large\displaystyle\text{$\begin{gathered}\sf \left.\begin{matrix} \blue{10692 }\\ \ 5346\\ \ 2673\\ \ \ \ 891\\ \ \ \ 297\\ \ \ \ \ 99\\ \ \ \ \ 33\\ \ \ \ \ 11\\ \ \ \ \ 1 \end{matrix}\right|\begin{matrix} 2\\ 2\\ 3\\ 3\\ 3\\ 3\\ 3\\ 11\\ \: \end{matrix} \end{gathered}$}[/tex]

[tex]\huge \red{\boxed{\green{\boxed{\boldsymbol{\purple{Pisces04}}}}}}[/tex]

Answer:

its 80

Step-by-step explanation:

the ratio is 80 hope this helps!

Answer:

740 miles

Step-by-step explanation:

$415-$230=$185

$185÷0.25 per miles =740 miles

Plug in the points and see if they satisfy the equation.

y = 2x - 3

(1, -1)

-1 = 2(1) - 3

-1 = 2 - 3

-1 = -1

So (1, -1) satisfies the equation.

(-3, 0)

0 = 2(-3) - 3

0 = -6 - 3

0 = -9

So (-3, 0) does not satisfy the equation.

(5, 4)

4 = 2(5) - 3

4 = 10 - 3

4 = 7

So (5, 4) does not satisfy the equation.

Therefore your answer is (1, -1).

Answer:

the answer is 5,4

a) The test statistic is given as t = [tex]\dfrac {14-12}{\dfrac{4.32}{\sqrt25}}}[/tex]= 2.315

b) The pa value will be P = P( t₂₄ > 2.315 ) = 0.015

c) If we compare the p-value and the significance level is given we see that  so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the true mean is higher than 12 at 1% of significance

In null hypotheses, there is no relationship between the two phenomena under the assumption that it is not associated with the group. And in alternative hypotheses, there is a relationship between the two chosen unknowns.

X= represents the sample mean

s = represent the sample standard deviation

n = 25 sample size  

[tex]\mu_o[/tex] = 12 represent the value that we want to test

[tex]\alpha[/tex] = 0.05 represent the significance level for the hypothesis test.  

t would represent the statistic (variable of interest)  

[tex]p_v[/tex] represent the p-value for the test (variable of interest)  

State the null and alternative hypotheses.  

We need to conduct a hypothesis in order to check if the mean is higher than 12, the system of hypothesis would be:  

Null hypothesis:  ≤ 12

Alternative hypothesis: > 12

If we analyze the size for the sample is > 30 but we don't know the population deviation so is better to apply a t-test to compare the actual mean to the reference value, and the statistic is given by:  

[tex]t=\dfrac{X-\mu_o}{\dfrac{\sigma}{\sqrt{n}}}[/tex]

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to a specified value".  

Calculate the statistic

We can replace in formula (1) the info given like this:  

[tex]\dfrac {14-12}{\dfrac{4.32}{\sqrt25}}}[/tex]= 2.315    

P-value:-

The first step is calculate the degrees of freedom, on this case:  

 df = n - 1 =25 - 1 = 2

Since is a one side right tailed test the p value would be:  

[tex]p_v[/tex] =  P( t₂₄ > 2.315 ) = 0.015

Conclusion  

If we compare the p-value and the significance level is given [tex]\alpha[/tex]= 0.05  we see that [tex]p_v < \alpha[/tex]  so we can conclude that we have enough evidence to reject the null hypothesis, so we can conclude that the true mean is higher than 12 at 1% of significance.

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Answer:

  B.  2x = y; 2x +1.5y = 20

Step-by-step explanation:

The two given relations can be written as two equations, one for the numbers of fish, and one for their cost.

__

The number of goldfish (y) is twice the number of tetras (x), so one equation can be ...

  2x = y

The tetras (x) are $2 each, and the goldfish (y) are $1.50 each. Their total cost is the sum of products of the number of fish and the cost of each. That total is given as $20, so the other equation could be ...

  2x +1.5y = 20

Then the appropriate system of equations is ...

_____

Additional comment

The solution can be found by substituting for 2x to get ...

  y +1.5y = 20 . . . . . . substitute for 2x

  y = 20/2.5 = 8 . . . . divide by the coefficient of y

  x = y/2 = 4 . . . . . . . find the number of tetras

Rick bought 4 tetras and 8 goldfish.

__

The wording "twice as many goldfish as tetras" easily causes confusion. It is helpful to reword it as "goldfish were twice the number of tetras."

A description of how the pattern is growing is that the pattern is growing by the addition of two blocks every time.

A numerical description of the pattern is:

1 - 2 blocks.

2 - 4 blocks.

3 - 6 blocks

4 - 8 blocks.

The formula that can be used to calculate the number if building blocks in any term will be 2n. For example, the number of blocks for the 5th term will be:

= 2n = 2 × 5 = 10

The value for the 10th frame will be:

= 2n

= 2 × 10 = 20

The value for the 100th frame will be:

= 2n

= 2 × 100 = 200

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The angles are: A =24.7° ; B = 40.6° ; C =114.7°.

The law of cosine helps in establishing a relationship between the lengths of sides of a triangle and the cosine of its angles. The cosine law in trigonometry generalizes the Pythagoras theorem, which applies to a right triangle.

Cosine Law

a² = b²+c²-2bc cos A

b² = c²+a² -2ca cos B

Sum of three angles of a triangle is 180°.

a = 34 ; b= 53; c = 74

Substituting the given values in the cosine law, we have

34² = 53² + 74² - 2*53 *74 * cos A

7844 cos A = 2809 + 5476 - 1156 = 7129

cos A = 7129/7844 = 0.9088

A = cos⁻¹ (0.9088) = 24.6600° = 24.7°

53² = 74² + 34² - 2 (74)(34) cos B

5032 cos B = 5476 + 1156 - 2809 = 3823

cos B = 3823/5032 = 0.7597

B = cos⁻¹ (0.7597) = 40.5622° = 40.6°

Also, A + B + C = 180°

24.7 + 40.6 + C =180

C =180 -  65.3 = 114.7°

Thus, the angles are: A =24.7° ; B = 40.6° ; C =114.7°

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The greatest height is 9 feet.

What is projectile?

A projectile is any object thrown into space upon which the only acting force is gravity.

As, from the graph we can see that

The highest point the ball reaches shown by the coordinates (0.75, 9)

As, the maximum height is shown by y- axis(vertical axis).

Hence, the greatest height is 9 feet.

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The expression written in equivalent form with a common denominator is -1/6

Fractions are written as ratio of two integers. For instance a/b is a fraction.

Given the sum of the fractions shown;

-3/4 and 5/8

Sum = -3/4 + 5/8

Sum = 5/8 - 3/4

Sum = 5-6/8

Sum  = -1/8

Hence the sum of the given fraction -1/3 and 5/8 is -1/6

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The true option about the system of linear equation is that the system can only be independent and consistent.

It should be noted that the system is consistent as it can illustrate more than a solution.

Also, it can't be independent and dependent at the same time as depicted in some of the option given.

In this case, true option about the system is that the system can only be independent and consistent.

The complete question is:

Given that (1, 0, 1) is a solution to a system of three linear equations, which of the following is true about the system?

The system can be either inconsistent or consistent.

The system can be either independent or dependent.

The system can only be independent and consistent.

The system can only be dependent and inconsistent.

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