How to solve

3x+2y=4
2x-3y=7

1 answer

3 x + 2 y = 4 Multiply both sides by 2

6 x + 4 y = 8

2 x - 3 y = 7 Multiply both sides by 3

6 x - 9 y = 21

6 x + 4 y = 8
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6 x - 9 y = 21
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6 x - 6 x + 4 y - ( - 9 y ) = 8 - 21

4 y + 9 y = 13

13 y = - 13 Divide both sides by 13

y = - 13 / 13 = - 1

Replace this value in equation:

3 x + 2 y = 4

3 x + 2 * ( - 1 ) = 4

3 x - 2 = 4 Add 2 to both sides

3 x = 4 + 2 = 6 Divide both sides by 3

x = 6 / 3 = 2

x = 2 , y = - 1