Question

help

Answer 1

\[ (a-b)^2 = a^2-2ab+b^2 \]
where
\[ a=4x \]
\( b=9 \)

by subtituting, we get:
\[ (4x)^2-(2 \times 4x \times 9)+9^2 \]
can you do the rest?

Answer 2

16x-?+81
its the middle i have trouble on
sorry i took so long to replied i was talking to someone

Answer 3

wait no 16x^2-?+81

Answer 4

yeah you're right -- so we have \( (16^2-(2 \times 4x \times 9)+81 \)
what is \( 2 \times 9 \) ?

Answer 5

oops -- i accidentally added a bracket in the beginning lol!

Answer 6

i was right(:

Answer 7

18

Answer 8

what about \( 18 \times 4x \) ?

Answer 9

72x

Answer 10

Yes! so our answer would be:
\( 16^2-72x+81 \)

Answer 11

ok thanks

Answer 12

you got it!