Question

find the x and y intercepts

f(x)=9x^2+24x+16

Help

Answer 1

let y = 9x^2 + 24x + 16
for the y-intercept , let x = 0 , --->y = 16

for the x-intercept, let y = 0
9x^2 + 24x + 16 = 0
you could use the quadratic formula, but I noticed the above is a perfect square, so
(3x+4)^2 = 0
3x+4 = 0
x = -4/3

So there is one x-intercept at x = -4/3

(the parabola has its vertex at (-4/3, 0) and crosses the y-axis at (0,16) )

Answer 2

This crosses the y axis when x=0 so

y=16

This crosses the x axis when y=0

0=9x^2+24x+16

0=(x+4/3)^2

so x=-4/3