Question

Find the value of the lesser root of x2 - 8x + 7 = 0

A) -1
B) 1
C) 3
D) 5

Answer 1

The correct answer is B

We can factor this first. We want factors of 7 that sum to -8; -7(-1) = 7 and -7+-1 = -8:

(x-1)(x-7)=0

Using the zero product property, we know that either x-1=0 or x-7=0. This gives us x=1 or x=7.

Explanation:

Answer 2

The correct answer is B) 1.

We can factor this first. We want factors of 7 that sum to -8; -7(-1) = 7 and -7+-1 = -8:
(x-1)(x-7)=0

Using the zero product property, we know that either x-1=0 or x-7=0. This gives us x=1 or x=7.