SOLUTION: Can you help me with this problem and help me sketch a graph y = x^2 + 2x -24 Thanks, M

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Question 23329: Can you help me with this problem and help me sketch a graph
y = x^2 + 2x -24
Thanks,
M
Answer by philberg99(10) About Me  (Show Source):
You can put this solution on YOUR website!
First of all, look at the coefficient of the x%5E2 term. If it is positive, then the parabola is shaped up. If it is negative, the parabola is shaped down. The coefficient of the x%5E2 term is 1 so it is shaped up.
Now we have to figure out where the parabola crosses the x axis. To do this, set the equation equal to zero.
0 = x%5E2+%2B+2%2Ax+-+24
0 = (x - 4)(x + 6)
0 = x - 4, 0 = x + 6
So x = 4, x = -6 are our solutions.
Finally, you may need to find the lowest point of this parabola, called the vertex. To find the x coordinate of the vertex, use the formula x = %28-b%29%2F%282%2Aa%29 where a is the coefficient of the x%5E2 term and b is the coefficient of the x term. So x = %28-2%29%2F%282%2A1%29%7D%7D%2C+so+x+=+%7B%7B%7B%28-2%29%2F2 = -1. To find the y value that goes with the -1, substitute -1 in for x. That gives us y = (-1)^2 + 2(-1) - 24 = 1 - 2 - 24 = -25. So the vertex, or the lowest point of the parabola is (-1, -25).