posted by mysterychicken on .
Need help with these---
30. Suppose the area of a square is x^2 - 6x + 9. What is the perimeter of the square?
33. Factor the expression: k^2 + k^f - 2f^2
38. Find the final amount of an investment if $2,000 is invested at an interest rate of 8% compounded quarterly for eight years.
30. If we factorise x^2 - 6x + 9, we get (x-3)^2.
So the perimeter is 4(x-3) = 4x -12
I'll need to figure out the others yet in a minute.
Wouldn't the perimeter be 4(x-3)^2?
Why? x-3 is the length of ONE side. To calculate
the perimeter of a square, the 4 identical sides are added. But maybe I'm wrong, I dunno....why do you want to square it?
Jazzie, you're correct. Thanks
30. 4x-12 is correct
33. You probably meant to type
k^2 + kf - 2f^2 which is
Amount = 2000(1.02)^32