Question

The sides of a rectangle have length x + 1 and width x - 5. Which equation below describes the area, A, of the rectangle in terms of x?
Select one:
a. A = x - 4
b. A = x2 + 6x - 5
c. A = x2 - 4x - 5
d. A = 4x - 8

Answer 1

C.

Side note: FOIL stands for First, Outer, Inner, Last
You use it when you're multiplying binomials (expression with two terms) together

For example:
(x+1)(x-5)

Step one: Multiply the FIRST terms by each other
x*x = x^2

Step two: Multiply the OUTER terms by each other
x*-5 = -5x

Step three: Multiply the INNER terms by each other
1*x = x

Step four: Multiply the LAST terms by each other
1*-5 = -5

Step five: Now, you get all the answers you got using the FOIL process, and add them together to create an expression.

x^2 -5x + x - 5

Step six: Combine like terms and simplify
X^2 -4x -5