Question

A student performed the following steps to find the solution to the equation

x²-2x-15-0. Where did the student go wrong?
Step 1. Factor the polynomial into (x + 3) and (x - 5)
Step 2. x+3 = 0 and x- 5 = 0
Step 3. x=3 and x = -5
A. in Step 1
B. in Step 2
C. The student did not make any mistakes, the solution is correct
OD. in Step 3

Answer 1

D

Explanation:

step 2 : x + 3 = 0 and x - 5 = 0 ← correct

step 3

x = 3 and x = - 5 ← error made here with signs, correct statement should be

x + 3 = 0 ⇒ x = - 3

x - 5 = 0 ⇒ x = 5