Question

S is directly proportional to the square of r. When r is increased by 200%
a) find an expression for the new r,
b) and the percentage increase in S

Answer 1

r is increased by 200%
2r+r=3r
s is directly proportional to r^2
New r is 3r
(3r)^2=9r^2
So S would increase by 9 times

Answer 2

Do you have the answers..?

Answer 3

I see, so I don't put the r^2 into the equation right? In question a?

Answer 4

because I'm not sure

Answer 5

Nah, it's alright