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The directions say "find the solution to the system of equations".
7x + 3y = -8
-4x - y = 6
asked Apr 10, 2013 in ALGEBRA 1 by rockstar Apprentice

2 Answers

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If the directions says then the addition method was used

The equations are 7x + 3y = -8 and -4x - y = 6 or -12x - 3y = 18

7x + 3y = -8

-12x - 3y = 18

-5x = 10

Divide each side by negitive 5

x = -2

Substitute x = -2 in the equation 7x + 3y = -8

7(-2) + 3y = -8

Add 14 to each side

3y = -8 + 14

3y = 6

Divide each side by 3

y = 2

The solution of the equation x = -2 and y = 2.

 

answered Apr 10, 2013 by diane Scholar
0 votes

 

7x + 3y = -8 ----------- (1)
-4x - y = 6 ------------ (2)

multiply by 3 both sides of the equation 2 and add with equation 1

7x + 3y = -8
-12x - 3y = 18
--------------------
-5x = 10

divide each side by -5
x = -2
substitute x = -2 in equation 2
-4 * -2 - y = 6
8 -y = 6
y = 2
(x, y) = (-2, 2)

answered Apr 13, 2013 by Naren Answers Apprentice

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