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OpenStudy (oraclethinktank):
Help please. I need to graph the Quadratic Equation y = -x^2 - 4x - 3
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OpenStudy (oraclethinktank):
So far I have
a= -x^2
b= -4x
c= -3
Following the rule of x= -b/2a
x= 4x/2(-x^2) = 4x/-2x^2 = - 2/x
OpenStudy (oraclethinktank):
Is the line of symmetry - 2/x?
OpenStudy (calculusxy):
Remember that a, b, and c are actually the numbers that are the coefficients.
For example in 2x^2 + 4x + 6 = 0
a = 2
b = 4
c = 6
OpenStudy (oraclethinktank):
So for my equation, they would be
a=2
b=-4
c=-3
OpenStudy (calculusxy):
In -x^2 - 4x - 3
a = -1
b = -4
c = -3
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OpenStudy (oraclethinktank):
So with that, using x=-b/2a would be 4/2?
OpenStudy (oraclethinktank):
Or 4/-2, rather.
OpenStudy (oraclethinktank):
Which in turn means that the Line of Symmetry for this equation is -2 since 4/-2 = -2
OpenStudy (calculusxy):
The axis of symmetry is
x = -(b)/2a
in this case you would have
x = -(-4)/2(-1)
x = 4/-2
x = -2
OpenStudy (oraclethinktank):
So I have that correct, What would come next for graphing the equation?
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OpenStudy (calculusxy):
Find the vertex by plugging back -2 into the quadratic equation to get the y value.
OpenStudy (calculusxy):
Then make a table with |dw:1470416782338:dw|
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