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2 years ago

4-5a+b=87a +9b = -32I need to use substitution for this one. Help?

Mathematics

1 answer:

Sauron [17]2 years ago

8 0

Answer:

Step-by-step explanation:

$\left\{\begin{array}{ccc}-5a+b=8&\text{add}\ 5a\ \text{to both sides}\\7a+9b=-32\end{array}\right\\\\\left\{\begin{array}{ccc}b=5a+8&(1)\\7a+9b=-32&(2)\end{array}\right\\\\\text{Substitute (1) to (2):}\\\\7a+9(5a+8)=-32\qquad\text{use the distributive property}\\\\7a+(9)(5a)+(9)(8)=-32\\\\7a+45a+72=-32\qquad\text{subtract 72 from both sides}\\\\52a=-104\qquad\text{divide both sides by 52}\\\\\boxed{a=-2}\\\\\text{Put the value of}\ a\ \text{to (1):}\\\\b=5(-2)+8\\\\b=-10+8\\\\\boxed{b=-2}$

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Select the correct answer from each drop-down menu.<br>Shape I is similar to shape II.

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Translation (moving the figure) will map figure 1 onto figure 2 and then after this , dilation by a scale factor of "2"

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3 years ago

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1<br> A=gh(B+b); A=20, B=4, b=1

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Answer:

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2 years ago

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In J, K is the midpoint. The coordinates of ) are (2, 2), and the coordinates of Kare (10, 11). What are the coordinates of L?

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Answer:

L(18, 20)

Step-by-step explanation:

In JL, K is the midpoint. The coordinates of J are (2, 2), and the

coordinates of K are (10, 11). What are the coordinates of L?

Solution:

If O(x, y) is the midpoint between two points A( $x_1,y_1$ ) and B( $x_2,y_2$ ). The equation to determine the location of O is given by:

$x=\frac{x_1+x_2}{2} \\\\y=\frac{y_1+y_2}{2}$

Since JL is a line segment and K is the midpoint. Given the location of J as (2, 2) and K as (10, 11). Let ( $x_2,y_2$ ) be the coordinate of L. Therefore:

$10=\frac{2+x_2}{2} \\\\20=2+x_2\\\\x_2=18$

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2 years ago

When asked to find a number one-tenth as large as another number, what operation would you use? What about when asked to find a

kherson [118]

Apply division by 10 when one tenth of a number is required and apply multiplication by 10 when 10 times of a number is required.

<u>Solution:</u>

Need to determine what operation is required to get one-tenth of a number and 10 times of a number

To get one tenth of a number, divide the number by 10.

For example to get one – tenth of 100, divide it by 10, we get 10 as a result.

$\frac{1}{10} \times 100 = 10$

To get ten times of a number, multiply the number by 10

For example 10 times of 10 = 10 x 10 = 100

Hence apply division by 10 when one tenth of a number is required and apply multiplication by 10 when 10 times of a number is required.

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2 years ago

Describe the sampling distribution of Phat. Assume the size of the Population is 25,000. N = 500 P = 0.4 Determine the Mean of t

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Answer:

0.022

Step-by-step explanation:

Given that :

Population size = 25000

n = 500 ; p = 0.4

Size of random sample (n) = 500

5% of population size : 0.05 * 25000 = 1250

Distribution is normally distributed since n < 5% of population size

Hence, the mean of the distribution = p = 0.4

Standard deviation = √((pq) /n)

q = 1 - p ; q = 1 - 0. 4 = 0.6

Standard deviation = √((0.4 * 0.6) /500)

Standard deviation = 0.0219089

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2 years ago

4-5a+b=87a +9b = -32I need to use substitution for this one. Help?​

4-5a+b=87a +9b = -32I need to use substitution for this one. Help?