7. Consider the rational expression x-4/x²-9 a. Evaluate the expression for x = 3.
b. Evaluate the expression for x = -2.
c. Explain why x=-2 is an acceptable value, but x=3 is not an acceptable value.

yes because there is exactly one y value for every x value

for function there can't be more than one value for every x value

step-by-step explanation:

y = | -2(-2) |     →     y = | 4 |     →     y = 4       ⇒   (-2, 4)

y = | -2(-1) |     →     y = | 2 |     →       y =   2       ⇒   (-1, 2)    

y = | -2(0) |     →     y = | 0 |     →       y = 0         ⇒   (0, 0)

y = | -2(1) |   c →     y = | -2 |     →     y =   2         ⇒   (1, 2)    

y = | -2(2) |     →     y = | - 4 |     →     y =   4         ⇒   (2, 4)  

step-by-step explanation: