Find the value of a so that the points A(6, 2a) and B(-a, -2) lie on a line having slope 7.
+2668 The slope formula is \({y_2 - y_1}\over{x_2-x_1}\).
We can write this as an equation: \({{2a + 2 } \over {6+a} }= 7\)
Multiply both sides by \(6 + a\),
Then solve for a.
