Question

Tricky one... Suppose that x* means 5x2 - x, then what does (y+3)* mean?

Answer 1

it means replace x in the first expression by
\[y+3\]

Answer 2

i.e. you get
\[(y+3)*=5(y+3)^2-(y+3)\] then you can clean it up with some algebra

Answer 3

Oh wow! So, (y+3)* = 5y^2+30y+45?
No further?

Answer 4

But -(y+3) I don't know how to subtract that from it...

Answer 5

Would (y+) and -(y+3) cross out?

Answer 6

Please help!! I think I have it..

(y+3)* = 5y+15

Answer 7

(y+3)* = 5y^2+30y+45 - (y + 3)

(y+3)* = 5y^2+30y+45 -1 (y + 3)

(y+3)* = 5y^2+30y+45 -y -3

(y+3)* = 5y^2 +29y - 42