Question

Which value of x must be excluded from the domain of the function, y = 9 / 2(x + 7)?
a) -2
b) -7
c) 2
d) 7

Answer 1

b) -7 because the dominator must be different by 0.

2(x + 7) ≠ 0    |divide both sides by 2

x + 7 ≠ 0    |subtract 7 from both sides

x ≠ -7