Question

Please help!!

Which expressions are differences of squares?

Select each correct answer.




t^2−1

p^2−40

n^2−225

k^2+81

Answer 1

• n2−225

• t2−1

Explanation:

Alright let's get it!

(WHOOP! WHOOP! WHOOP! WHOOP!)

First let's start with:

How can the difference of squares be written?

a^2 − b^2

This will be our friend for a while!!!

STEP 1:

Now let's start with the first problem:

t^2 − 1

It can be rewritten as,

t^2 − 1^2

Therefore choice 1 works!

STEP 2:

Next one:

p^2 − 40

The number 40 is not a complete square of any number, therefore choice 2 is not correct.

STEP 3:

Almost there!

n^2 − 225

It can be rewritten as,

n^2 − (15)^2

It is the difference of squares, therefore choice 3 is correct!!!

STEP 4:

Last one!!!!!

k^2 + 81

It can be written as,

k^2 + 9^2

It is the sum of squares, therefore the last choice is incorrect.

So......

The correct ones are:

• n2−225

• t2−1

Yassss, we survived!

So happy we got to do this together!

Hope this helps!!!