N is a multiple of 5 A = N + 1
B = N – 1
Prove, using algebra, that A2 – B2 is always a multiple of 20

Proved

Step-by-step explanation:

Given

Required

Prove that is a multiple of 20

First, we need to evaluate

Start by applying difference of two squares

Substitute values for A and B

Collect Like Terms

Since, N is a multiple of 5, then the possible values of N are:

For each of these values, the possible values of are

The above shows that is a multiple of 20

step-by-step explanation:

hjkj

b

step-by-step explanation:

multiply terms on numerator/ denominator by (x - 1)

= ← distribute numerator/ denominator

= ← simplify

=

= → b