Answer
a) $x^{2}$ + 2x
b) Both expressions for the area give the same answer. One simply finds the area as one complete rectangle, and the other finds the area as the combined area of the two smaller rectangles.
Work Step by Step
To find another expression for the area of the rectangle by, simply use the distributive property on the original expression.
x $\times$ x = $x^{2}$
x $\times$ 2 = 2x
$x^{2}$ + 2x