Question

find x,y intercepts..f(x)=-x^2+7x+30. I know y just need help with x

Answer 1

Find the y intercept by letting x = 0. Find the x intercepts by letting y = 0.

Answer 2

x^2+7x+30 = 0
Find two possible values of x.

Answer 3

do i need to factor first? cuz if i do i dont know what to put for 30

Answer 4

Use the formula.

Answer 5

yea i gotta find two points for x

Answer 6

f(x)=-(x^2-7x-30)=-(x-10)(x+3)=0 x=10, -3

Answer 7

wait would it be 10 and 3?

Answer 8

No, that gives -30 not +30. Unless the problem is wrong.

Answer 9

No. 10 and -3

Answer 10

oh yes -3

Answer 11

Factor out the negative 1 as I showed and then factor x^2-7x-30

Answer 12

so when i factor do i just not do the 7x?

Answer 13

10 and -3 are NOT right if the problem is x^2+7x+30=0.

Answer 14

You are factoring this trinomial: x^2-7x-30

Answer 15

and the y intercept is 30?

Answer 16

The problem is - x^2+7x+30

Answer 17

wait if it was minus it would be 10,-3?

Answer 18

Got it. I missed that. Thanks!

Answer 19

yw

Answer 20

ok i got confused for a minute

Answer 21

All I know is that the problem you posted said: f(x)=-x^2+7x+30 and the answers to that problem are 10 and -3 and I have shown you how to do it.

Answer 22

um yea thats the answer i got, thanks