Algebra Area Question

Question

A square has side lengths (x + 5) units. What is the area?

A. x² + 25 square units

B. x² - 25 square units

C. x² +10x +25 square units

D. x² - 10x +25 square units

Answer 1

This problem asks us to use our knowledge of the area of a square, as well as our ability to expand an equation

The area of a square is found by calculating the square of the sides, in other words A=(s)^2. We can then substitute in our side length of x+5 to get the equation A=(x+5)^2. This can also be written as A=(x+5)*(x+5).

We can then expand the equation by multiplying the terms and adding our products together, so A= x*x+5*x+5*x+5*5=x^2+10x+25

We see that the correct answer is C) x^2+10x+25

Answer 2

C) area = (x+5)^2

= (x+5)(x+5) = x^2+10x+25

Use FOIL

(x+5)(x+5) = x^2 +5x +5x +25 = x^2 +10x +25