4x+5y=-13;5x-2y=-8 solve elimination method Step by step

1 answer:

8 0

4x + 5y = -13
2(4x + 5y) = 2(-13)
8x + 10y = -26 (equation 1)

5x - 2y = -8
5(5x - 2y) = 5(-8)
25x - 10y = -40 (equation 2)

equation 1 + equation 2,
(8x + 10y) + (25x - 10y) = (-26) + (-40)
8x + 10y + 25x - 10y = -26 + -40
33x = -66
x = -2

substitute x = -2 into equation 1,
8x + 10y = -26
8(-2) + 10y = -26
-16 + 10y = -26
10y = -10
y = -1

The values of x and y are -2 and -1 respectively.

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