Question

Multiply and simplify (a-3b)^2

Answer 1

( a - 3b ) ( a - 3b )

= a² - 3ab - 3ab + (-3b)²

= a² - 6ab + 9b²

Answer 2

Simple,

distribute the
`^(2)`

It may seem tricky..there is a hidden term in there that most people would forget....

but, it's saying multiply (a-3b)(a-3b) (FOIL)

a*a=
`a^(2)` (First)

-3b*a= -3ab (Outer)

-3b*a= -3ab (Inner)

-3b*-3b= 9
`b^(2)` (Last)

Making it....


`a^(2)+-3ab+-3ab+9 b^(2)`

Combine terms...

Making your answer,
`a^(2) -6ab+9 b^(2)`