Question

Find the zeros and the y-intercept of:

f(x) = 6x^2 + 18x + 30

Please make sure to show how you did it.
Please help! I've literally been doing this all day!

Answer 1

The y-intercept exists when x = 0, so the y-intercept is (0, 30). The zeroes are found by factoring. You can simplify that a bit by factoring out a 6:
`f(x)=6( x^(2) +3x+5)`. Now factor that using the quadratic formula because the solutions are not real.
`x= \frac{-3+/- \sqrt{(3) ^(2)-4(1)(5) } }{2}` which simplifies to
`x= (-3+/- √(-11) )/(2)` and in the end we have
`x= (-3+/-i √(11) )/(2)`