anonymous
  • anonymous
find the vertex and the x intercepts of y = x2 + 6x − 16??
Mathematics
  • Stacey Warren - Expert brainly.com
Hey! We 've verified this expert answer for you, click below to unlock the details :)
SOLVED
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
schrodinger
  • schrodinger
I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!
anonymous
  • anonymous
|dw:1371220635595:dw|
anonymous
  • anonymous
|dw:1371220792989:dw|
anonymous
  • anonymous
|dw:1371220826248:dw| Then what?

Looking for something else?

Not the answer you are looking for? Search for more explanations.

More answers

Jim766
  • Jim766
-6/2 = ?
anonymous
  • anonymous
-3?
phi
  • phi
match a, b, c of \[ a x^2 + b x + c \] to your problem
Jim766
  • Jim766
right now sub it in to find the y part of the vertex y = x2 + 6x − 16
phi
  • phi
if there is no number in front of a letter (as in x^2) it is understood to be 1
Jim766
  • Jim766
y = (-3)^2 + 6(-3) -16
anonymous
  • anonymous
so +9-18-16?
Jim766
  • Jim766
right, keep going...
anonymous
  • anonymous
-27=y?
Jim766
  • Jim766
close, but not what I got...
anonymous
  • anonymous
9-18=-11 right?
Jim766
  • Jim766
9-18 = -9
anonymous
  • anonymous
ohhhhhhhh right okay
anonymous
  • anonymous
so -25=y!
Jim766
  • Jim766
so that is the y part of the vertex and you found the x earlier put them together to show your point (x, y)
anonymous
  • anonymous
(-3,-25)?
Jim766
  • Jim766
very nice!
anonymous
  • anonymous
Thank you!!! :DDD
Jim766
  • Jim766
now to find the x intercepts, you need to factor and solve do you need help with that?
anonymous
  • anonymous
factor y = x2 + 6x − 16, right?
Jim766
  • Jim766
yeah, keep in mind the x intercept is where y = 0 so, 0 = x^2 + 6x -16
Jim766
  • Jim766
0 = (x )(x )
anonymous
  • anonymous
Okay so 0=(6-4)(x+4x^2)?
Jim766
  • Jim766
think if it this way we are looking for two things we can mult together to get x^2 + 6x -16 I know that x * x = x^2 ( x )(x ) now what 2 numbers can I mult to get -16 but also add them together and get +6
anonymous
  • anonymous
okay... uhh 4*-4 equals -16 but i dont think it can equal 6
Jim766
  • Jim766
good, keep going ...how else can you make -16 by multiplying?
anonymous
  • anonymous
8*2
Jim766
  • Jim766
right !
anonymous
  • anonymous
Is that it?
Jim766
  • Jim766
which one has to be negative to add them together and get +6 -8*2 or 8 * -2
Jim766
  • Jim766
which pair adds to + 6
anonymous
  • anonymous
it's (x+8)(x-2) i think!
anonymous
  • anonymous
oh wait
anonymous
  • anonymous
No its vice versa xD
Jim766
  • Jim766
good! (x + 8)(x -2) = 0 now use zero prod property to solve each
anonymous
  • anonymous
How do you do that?
Jim766
  • Jim766
no, you were correct
anonymous
  • anonymous
Yay!
Jim766
  • Jim766
0 = x^2 + 6x -16 0 = (x +8)(x -2) zero prod property says that when two things are mult together and equal zero, that one or both must equal zero, so that gives us the right to do this x + 8 = 0 or x -2 = 0 now solve each of these to find the x intercepts
anonymous
  • anonymous
so 8x=0 or -2x=0?
Jim766
  • Jim766
x + 8 = 0 -8 -8 x = -8 one x intercept is -8
Jim766
  • Jim766
x -2 = 0 solve this one
anonymous
  • anonymous
x-2=0 +2 +2 answer is +2!
Jim766
  • Jim766
right! so the x intercepts are { -8, 2} , or another way to write it x = -8 or x = -2
Jim766
  • Jim766
there are other ways to find the x intercepts of a quadratic... because factoring will not always work, but this is usually the first way they show you
anonymous
  • anonymous
Oh my god thank you so much :D you are super helpful!!
Jim766
  • Jim766
yw glad to help

Looking for something else?

Not the answer you are looking for? Search for more explanations.