Question

Two regular octagons have areas of 48 mm² and x² + 8x mm². What values of x make the octagons congruent?

Answer 1

x^2+8x=48 <- set the two areas equal to each other
x^2+8x-48=0 <- subtract 48 from both sides
(x-4)(x+12)=0 <-factor them out
The last step is up to you! It'll give you the two final numbers, just solve for x!

Answer 2

but the length cannot be negative.. So answer would be x= 4...

Answer 3

my answers say 4 and 12 or 4 and -12

Answer 4

It's not asking for the length, just the values of x that make them congruent :D So any number can be x

Answer 5

@stephstar101 : hmmm, yes any value can make it congruent.. @mr.perkins: so its 4 & -12..

Answer 6

sorry, @mrs.perkins

Answer 7

ok thank you