Question

Use the Perfect Square Trinomial and provide the first step to calculating 382 without a calculator.

(40 − 2)2
(40 + 2)2
(29 − 9)2
(29 + 9)2

Answer 1

(40 − 2)^2

Explanation:

(First just do simple math to narrow down your choices)

A: (40 − 2)^2

40 - 2 = 38

B: (40 + 2)^2

40 + 2 = 42

C: (29 − 9)^2

29 - 9 = 20

D: (29 + 9)^2

29 + 9 = 38

(Now you just have A and D)

A: (40 − 2)^2

D: (29 + 9)^2

(Determine which properly expresses a Perfect Square Trinomial)

A: (40 − 2)^2

I just took the test.

Answer 2

`(40-2)^2`

Explanation:

Given:
`(38)^2`

To find: the correct option

Solution:

A binomial polynomial is a polynomial consisting of two terms.

A trinomial polynomial is a polynomial consisting of three terms.

On multiplying a binomial
`(x-y)` to itself, a perfect square trinomial
`(x-y)^2` is obtained.

Here,
`38=40-2`

So,
`(38)^2=(38)(38)=(40-2)(40-2)=(40-2)^2`

Here,
`(40-2)` is a binomial and it is multiplied to
`(40-2)` to get a perfect square trinomial
`(40-2)^2`