Question

A rectangular photograph is mounted on a square price of cardboard whose sides have lengthy x. The border that surrounds the photos is 3 inches on each side and 4 inches on both top and bottom. Which expressions represent the area of the photograph

Answer 1

X= sides of square (all sides are equal)
(x-3)= length of rectangle
(x-4)= width of rectangle

Area of rectangle= length x width
A= (x-3)(x-4)

multiply each term in the left parentheses by each in the right
A= (x*x) + (x*-4) + (-3*x) + (-3*-4)

A= x^2 -4x -3x + 12
combine like terms

A= x^2 -7x + 12 Area of the photograph

Hope this helps! :)