Question

Sam decides to build a square garden. If the area of the garden is 25x2 + 30x + 9 square feet, what is the length of one side of the garden?

Answer 1

The correct answer is C. (5x+3) feet, and here is how I got it.

This is the equation you need to use:

(a+b)^2 = (a+b) (a+b)

So, let us plug in 5x and 3 here:

(5x+3)^2 = (5x+3)(5x+3) = 25x^2 + 15x + 15x + 9 = 25x^2 + 30x + 9 which is the area of the garden.

Answer 2

5x + 3

Explanation:

We factor 25x^2 + 3x + 9.

25x^2 is a perfect square; 25x^2 = (5x)^2

9 is a perfect square; 9 = 3^2

This expression may be a perfect square trinomial.

25x^2 + 30x + 9 = (5x + 3)^2

We check the middle term: 2ab = 2 * 5 * 3 = 30

The coefficient, 30, is correct, so we are dealing with a perfect square trinomial.

length = 5x + 3