Question

Use elimination to solve the system of equations given by -7x + 3y = 14 and 7x - 2y = -14.

Answer 1

The coefficients of x are already opposites, so you can simply add the two equations to eliminate x.

... (-7x +3y) + (7x -2y) = (14) + (-14)

... y = 0 . . . . . . . simplify

... -7x + 3·0 = 14  . . . . substitute the value of x into the first equation

.. x = 14/(-7) = -2

The solution is (x, y) = (-2, 0).