y = 3 - x. this is equation 1 8x + y = -4. this is equation 2 since equation 1 already defined the value of y in terms of x, we can substitute it into 2 8x + 3 - x = -4 7x = -7 x = -1 as x = -1, substitute it back into equation 1, y = 3 - (-1) y = 3 +1 y = 4
