college algebra
posted by kirs .
y intercept:
3x^2+18x
0=3x^2+18x
from here im lost

what do you want to do?
solve it ?
find the yintercept ? 
yes find y intercept

then let x = 0
so y = 3(0) + 18(0) = 0
the yintercept is 0, the line runs through the origin. 
sorry i meant the x intercept

x intercept:
y = 3x^2+18x
0 = 3x^2+18x
3x is common to both terms on the right: factor it out.
0 = 3x(x + 6)
If 2 values are multiplied together and the product is 0, then one or both of the values must be 0.
3x = 0 and/or x + 6 = 0
Take it from there.