Question

Multiply: (m + 7) (m - 7) the 7 crosses out right? so is the answer m^2-49?

Answer 1

m^2 - 49 is right!

Answer 2

But what 7 crossing out ? o.O

Answer 3

Another tip. There's an identity - \((a + b)(a - b) = a^2 - b^2\)

Answer 4

(a + b)(a - b) = \[a^2 - b^2\]

Therefore,
answer will be :\[m^2 - 49\]...