Find A so that the function is continuous at 4.

Question

f(x) = x² , x<4

Ax-8 , x>=4

A = ____

Answer 1

A=6

4A - 8 = 4^2

4A = 16+8 = 24

A = 24/4 = 6

Answer 2

If it's continuous, then the value of x² and Ax - 8 must be the same for x = 4 so:

(4)² = A(4) - 8

16 = 4A - 8

24 = 4A

A = 6