SOLUTION: Which statement must be true if a parabola represented by the equation y = ax^2 + bx + c does not intersect the x-axis? b^2 – 4ac = 0 b^2 – 4ac < 0 b^2 – 4ac > 0, and b^2 –

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Question 253299: Which statement must be true if a parabola represented by the equation y = ax^2 + bx + c does not intersect the x-axis?
b^2 – 4ac = 0
b^2 – 4ac < 0
b^2 – 4ac > 0, and b^2 – 4ac is a perfect square.
b^2 – 4ac > 0, and b^2 – 4ac is not a perfect square

Found 3 solutions by drk, Alan3354, JimboP1977:
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
The answer is:
b2 – 4ac < 0
This will give you a negative discriminant which means imaginary or no solutions.

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
b2 – 4ac < 0
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This is covered well by the on-site solver:
Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B12x%2B40+=+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=%2812%29%5E2-4%2A1%2A40=-16.

The discriminant -16 is less than zero. That means that there are no solutions among real numbers.

If you are a student of advanced school algebra and are aware about imaginary numbers, read on.


In the field of imaginary numbers, the square root of -16 is + or - sqrt%28+16%29+=+4.

The solution is x%5B12%5D+=+%28-12%2B-i%2Asqrt%28+-16+%29%29%2F2%5C1+=++%28-12%2B-i%2A4%29%2F2%5C1+, or
Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B12%2Ax%2B40+%29




Answer by JimboP1977(311) About Me  (Show Source):