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Solve this system of linear equations. Separatethe x- and y-values with a comma.-9x + 3y = 39-7x + 2y = 33

User Chris Frank
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1 Answer

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26 votes
Answer:

The solution to the system of equations is:

(x, y) = (-7, -8)

Step-by-step explanation:

Given the pair of equations:

-9x + 3y = 39 .....................................................(1)

-7x + 2y = 33 .....................................................(2)

Multiply (1) by 2

-18x + 6y = 78 ....................................................(3)

Multiply (2) by 3

-21x + 6y = 99 ..................................................(4)

Subtract (4) from (3)

-18x - (-21x) = 78 - 99

-18x + 21x = -21

3x = -21

x = -21/3 = -7 ......................................................(5)

Using (5) in (1)

-9(-7) + 3y = 39

63 + 3y = 39

3y = 39 - 63 = -24

y = -24/3 = -8

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User GScrivs
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