How do you write the expression for the area given the length (x+6) and width (x-3)?

1 Answer
Nov 23, 2016

For a rectangle the expression would be: #A = (x + 6) * (x - 3)# or #A = x^2 - 3x - 18#

Explanation:

The formula for area (assuming this is a rectangle) is:

#A = l * w# where #A# is the area of the rectangle, #l# is the length of the rectangle and #w# is the width of the rectangle.

In this problem we are provided the length and width which we can substitute for the #l# and #w# is the formula to give:

#A = (x + 6) * (x - 3)#

We can expand this to the form of a quadratic equation by cross multiplying to give:

#A = x^2 + 6x - 3x - 18#

#A = x^2 - 3x - 18#