# Multiplying monomials to findÂ area

CCSS Math: HSA.APR.A.1, HSA.SSE.A.1

## Video transcript

Express the area of a rectangle
with the length 4y and width 2y as a monomial. So the area of a
rectangle is just the width times the height,
or the base times the height. Now here, the base is 4y. So let me just
write it down-- area is going to be
equal to the width of the base times the height. The width is 4y and
the height here is 2y. So the area is going
to be 4y times 2y. Now here we can just
use the associative and the commutative
properties of multiplication. So just swap the order that
we do this multiplying in. Instead of multiplying 4
times y times 2 times y, we could say this is the same
thing as 4 times 2 times y times y. And of course, 4 times 2,
that part right over there is just equal to 8. And then y times y, well
that's just y squared. Or it's y to the first
times y to the first, which is also y squared. So it becomes 8y squared. So that's the area
and it's a monomial. This is a polynomial
with only one term.