SOLUTION: y= x2 + 4x - 7 what is the : y - intercept x - intercept turning point please write down the solution as well, thanks

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Question 233554: y= x2 + 4x - 7
what is the :
y - intercept
x - intercept
turning point
please write down the solution as well, thanks

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
y= x2 + 4x - 7
.
y intercept (x=0) = -7
.
x intercept (y=0):
x^2+4x-7=0
x^2+4x =7
x^2+4x+4=7+4 completing the square.
(x+2)^2=11
x+2=+-sqrt(11)
x=-2+sqrt(11), x=-2-sqrt(11)
.
x^2+4x-7
=(x^2+4x+4)-4-7 completing the square again.
=(x+2)^2-11 standard form of the quadratic.
=a(x-h)^2+k standard form of the quadratic.
The vertex is (h,k)=(-2,-11)
.
Ed
.
graph%28500%2C500%2C-10%2C10%2C-12%2C8%2Cx%5E2%2B4x-7%29