SOLUTION: find the x and y intercepts: y = x squared + 8x + 14

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Question 167601: find the x and y intercepts:
y = x squared + 8x + 14

Found 2 solutions by Mathtut, Alan3354:
Answer by Mathtut(3670) About Me  (Show Source):
You can put this solution on YOUR website!
this is a parabola the y intercept is found setting x's value to zero
so y intercept is 14 or (0,14)
the x intercepts are found by setting y=0
so we have x%5E2%2B8x%2B14 using the quadratic formula we come up with x intercepts of -2.59 and -5.41 or (-2.59,0)and (-5.41,0)
Quadratic equation (in our case ) has the following solutons:


For these solutions to exist, the discriminant should not be a negative number.
First, we need to compute the discriminant : .
Discriminant d=8 is greater than zero. That means that there are two solutions:




Quadratic expression can be factored:
Again, the answer is: -2.58578643762691, -5.41421356237309. :


Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
find the x and y intercepts:
y = x squared + 8x + 14
-----------------
To find the y-intercept, set x=0
y = 14, so it's (0,14)
Finding the x-intercepts is solving for x
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B8x%2B14+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%288%29%5E2-4%2A1%2A14=8.

Discriminant d=8 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-8%2B-sqrt%28+8+%29%29%2F2%5Ca.

x%5B1%5D+=+%28-%288%29%2Bsqrt%28+8+%29%29%2F2%5C1+=+-2.58578643762691
x%5B2%5D+=+%28-%288%29-sqrt%28+8+%29%29%2F2%5C1+=+-5.41421356237309

Quadratic expression 1x%5E2%2B8x%2B14 can be factored:
1x%5E2%2B8x%2B14+=+%28x--2.58578643762691%29%2A%28x--5.41421356237309%29
Again, the answer is: -2.58578643762691, -5.41421356237309. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B8%2Ax%2B14+%29

To clarify, the x-intercepts are:
-4+%2B+sqrt%282%29 and
-4+-+sqrt%282%29