Question 67692: Solve the following equation for x. Hint: Factor the left hand side. [Do not report answers in decimal – leave them in radical form, and be sure to simplify radicals.
x^2 + 4x + 4 = 7
I have come up with x = 2 +or- sqrt7. Is this a correct answer??? I would appreciate if someone could let me know howe I am doing. Thanks.
Answer by brandonpark2889(31)   (Show Source):
You can put this solution on YOUR website! Solve the following equation for x. Hint: Factor the left hand side. [Do not report answers in decimal – leave them in radical form, and be sure to simplify radicals.
x^2 + 4x + 4 = 7
I have come up with x = 2 +or- sqrt7. Is this a correct answer??? I would appreciate if someone could let me know howe I am doing. Thanks.
Well... first, of all, the right hand side MUST be 0, if you want to factor it.
So...  . Subtract 7 on each side:  . It ends
up with=  . Now factor this: this turns to: (x+3)(x-1)=0.
Now think. If x=-3, then it would be (-3+3)(-3-1)=0, right? Simplify that,
then it becomes 0=0. how did I think of x=-3? That's because I thought of
Zero Product Property. Concentrate on (x+3). If you get the opposite of +3,
wouldn't it be -3? and -3+3=0... and 0(-3-1)=0... 0x-4=0... then when you simplify that, the result would be: 0=0. But there are
actually 2 answers. Think of (x-1) now. Repeat this process... x could also
equal 1. So x={-3,1}... not x= 2 +or- sqrt7 :P
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I love math. Do you?
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