1. 3x + 2y = 4
2. -7x + 2y = 24

finding x and y.

Derek
student
cheers!



Hi Derek,

These two equations are particularly nice because the coefficient of y is the same in both. I would first multiply both sides of the second equation by -1 to get

3x + 2y = 4
7x - 2y = -24 Since 3x + 2y = 4 and 7x - 2y = -24, (3x + 2y) + (7x - 2y) = 4 + (-24) and hence 10x = -20

Solve this equation for x, substitute the value into either of the equations you started with, and solve for y.

Cheers,
Penny

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