Question

What value of X in the point (x, -3) makes 2x -y =9 true?

Answer 1

(x, -3)

2x - y = 9      Plug in the point into the equation (x stays the same since there isn't a value for it)

2x - (-3) = 9

2x + 3 = 9     Subtract 3 on both sides

2x = 6     Divide 2 on both sides

x = 3   (3, -3)