Question

find the x-intercept of the parabola with vertex (4,-1) and y- intercept (0,15). write answer in (x1,y1) (x2,y2) form :D

Answer 1

vertex (4,-1)

y =a(x-4)^2 -1

using y-intercept pt(0,15) to find a

15 = a(-4)^2 - 1

16 = a*16




1 = a

y = (x-4)^2 - 1 OR y = x^2 - 8x + 15

x^2 - 8x + 15 = 0

factoring

(x-3)(x-5) = 0

(x-3) = 0 x = 3

(x-5) = 0 x = 5

x-intercepts are Pt(3,0) and pt(5,0)

Answer 2

do i put (3,0),(5,0) or (3,0) (5,0) ?

Answer 3

your answer is both (3,0) and (5,0)

Answer 4

WOOOOOOOOOOOOOOO it was correct

Answer 5

oh good
you had me worried there for a sec

Answer 6

lol :) thanks so muchhh <33 but i have another one now :( u dont needa do the entire work; i just need the answeer :)

Answer 7

i was giving you the work, so you could do the next one mostly yourself

its not like you're dumb or anything

Answer 8

the thing is that i am :( thats why im in summer school lol. well can u help me? like give me directtions?

Answer 9

yes
but please dont rush me i have to do other work too

Answer 10

no rushing ^_^ <3 just tell me here when u can help me.

Answer 11

its probably better to post the question anyway, cause theres a fair few people on here that could help you ... not just 12 year olds :)

i've been getting help with my calculus/matrices/ stuff you learn in college

Answer 12

i did post it but no one is helping me :( & omg thats cool. thanks for the help anyways.