Question

Solve each of the following equations
a. (x - 1)(x + 1) = 15​

Answer 1

Step-by-step explanation:

(x-1)(x+1) = 15

x^2 - 1^2 = 15

x^2 = 15 + 1

x^2 = 16

x = 4

Answer 2

Answer:

(x-1)(x+1) = 15

(a-b)(a+b) = a^ 2-b^2.

(x-1)(x+1) = x^2-1^2 = x^2-1

x^2-1=15

x^2=15+1

x = √16

therefore x = 4.