HELP! MEDAL? find the x-intercept of the parabola with vertex (1,1) and y intercept (0,-3) write your answer in this form: (x1,y1),(x2,y2) if necessary round to the nearest hundredth
you can find the equation of the parabola then find the x-intercepts
\[y=a(x-h)^2+k \] you are given (h,k) already plug that in you can solve for a by using the other point then to find the x-intercepts you set y to 0 and solve for x
@Love.Kat123 let me know if you have any questions
im confused by it all math isnt my strong suit
do you know what h and k are?
(h,k) is the vertex you are given h=? and k=?
you are given the vertex is (1,1) (1,1)=(h,k) so h=? and k=?
1?
both are 1 yes so plug those in \[y=a(x-h)^2+k \\ y=a(x-1)^2+1\]
now find a using the other point
(x,y)=(0,-3) so replace x with 0 and y with -3 and solve for a
ugh im so confused and frustrated i have no idea what your talking about im legit going to cry
you should see see an x and y in my equation above
I'm asking you to replace x with 0 and y with -3
then solve for a
please show me as far as you can get with my last instruction
i can get about as far as reading the question i should have taken those classes more seriously
\[\color{red}y=\color{green}a(\color{blue}x-1)^2+1\] do you see the x and the y there? we are trying to use x=0 and y=-3 to find a
like can you at least replace the x with 0 and the y with -3?
like that is all I'm asking you to do right now just one step ... replacing x with 0 and y with -3
yes... maybe ... i think
can you show me what you have please
wait is x1 0 and y1 -3
though that is a y-intercept not an x-intercept
Can you please replace the x in my equation with 0 and replace the y in my equation with -3
\[\color{red}y=\color{green}a(\color{blue}x-1)^2+1 \] the y is in red the x is in blue
replace that blue letter with 0 replace that red letter with -3
okay so -3=a(0-1)^2+1
great so notice you have enough information to solve for a
wait is that right
it doesnt say anything about a
oh my im going to fail D:
yes it does... you even typed a... see the a in -3=a(0-1)^2+1
first let's do the operation next to a (0-1)^2=?
uh.... what
if you take 1 away from 0 you have -1... (-1)^2=?
i think im going to have a panic attack
you are going to have a panic attack over me asking you to evaluate (-1)^2? why?
(-1)^2 is the same as saying -1 times -1
I know you can do that
but the just equals -1 :|
-1 times -1 isn't -1 \[-3=a(0-1)^2+1 \\ -3=a(-1)^2+1 \\ \\ -3=a(1)+1 \\ -3=a+1\]
-1 times -1 is 1
anyways solve -3=a+1 for a
okay um a=-2
how did you get -2?
subtract 1 on both sides gives -3-1=a+1-1 or -3-1=a
-3-1 is?
you said -3=a+1 -3+1=-2
-3-1=-4
you cannot solve for a that way
you cannot subtract 1 on one side and do the oppsite to the other other side
-3=a+1 gives us a=-3-1 not -3+1
anyways yet a=- 4 since -4+1 is -3
\[y=a(x-h)^2+k \text{ is vertex form for a parabola } \\ (h,k)=(1,1) \\ y=a(x-1)^2+1 \\ \text{ we used} (0,-3) \text{ to find } a \\ \\ a=-4 \\ y=-4(x-1)^2+1 \\ \text{ we now have everything we need to find the } x-\text{intercepts }\]
so to finally find the x-intercepts we set y to 0 and solve for x
x-intercepts lay on the x-axis this is why y is 0 there
so you already have the y-coordinates for both your answers we are looking for the x-coordinates
and again to find those replace y with 0 and solve for x
whats a x-axis
the horizontal axis that is also know as the line y=0
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