Perform the indicated operations and simplify the expression? (7u - 4v)(7u + 4v)?

Answer 1

This is a difference of squares, so when you distribute the first time the middle two terms should add to 0.

(7u - 4v)(7u + 4v)

Distribute 7u and -4v to both terms.
49u^2 + 28uv - 28uv - 16v^2

Collect like terms.
49u^2 - 16v^2

Answer 2

Did you notice that it is in the form (a+b)(a-b)? This is the factored form of the difference of two squares and will always equal a^2-b^2. in this case, 7u is a and 4v is b, so, a^2=(7u)^2=49u^2 and b^2=4v^2=16v^2. thus, 49u^2-16v^2.

I hope that helps.

Answer 3

given (7u-4v)(7u+4v)
first you expand the equation,
=7u(7u+4v)-4v(7u+4v)
=49u^2+28uv-28uv-16v^2
you'll get:
=49u^2-16v^2

Answer 4

49u^2+28uv-28uv-16v^2
=
49u^2 - 16v^2