i dont under atand this

Question

Evaluate the indicated function for f(x) = x² − 1 and g(x) = x − 7 algebraically. If possible, use a graphing utility to verify your answer.

(f − g)(-7)

Answer 1

(f - g)(-7)
= f(-7) - g(-7)
= [(-7)^2 - 1] - [-7 - 7]
= [48] - [-14]
= 62