4. (06.02 lc) line ef has an equation of a line y = −2x + 7. which of the following could be an equation for a line that is perpendicular to line ef? (6 points) y = 2x − 3 y = 1 over 2 x − 3 y = −2x − 3 y = − 1 over 2 x − 3

First, lets break down the sample equation: y=-2x+7
-2=m=slope
+7=b=Y-intercept

Using process of elimination:
A is not perpendicular because the angle created by slopes is unequal to 90
B and D are quadratic equations, and have no correlation with the sample equation
C is parallel to the sample equation

Is there a typo in your question? None of these answers are correct, but I am wiling to keep helping you, I enjoy Algebra. 

The answer would be -3.9> -4.5