Ok, so the function form is y = a * bx. Substitute in the values: 750 = a * b5 and 48 = a * b2 Then divide the two equations: 750/ 48 = (a * b5) / (a * b2) So: 15.625 = b3 Take the cube root of both sides: 2.5 = b Now, substitue b into one of the equations (the one with 48 has smaller numbers and is easier to work with.) 48 = a * 2.52 Simplify. 48 = a * 6.25 Divide both sides by 6.25 7.68 = a Now substitute in a and b to write the exponential function: y = 7.68 * 2.5x