SOLUTION: can you help me solve by using the quadratic formula of x^2-4x-5=0?

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Question 63113This question is from textbook
: can you help me solve by using the quadratic formula of x^2-4x-5=0? This question is from textbook

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
can you help me solve by using the quadratic formula of x^2-4x-5=0?
:
Here it is step by step:
:
In the form ax^2 + bx + c = 0; your problem: a=1; b=-4; -5
:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
:
x+=+%28-%28-4%29+%2B-+sqrt%28+%28-4%29%5E2-4%2A1%2A-5+%29%29%2F%282%2A1%29+
:
x+=+%28%2B4+%2B-+sqrt%28+16+-+%28-20%29+%29%29%2F%282%29+
:
x+=+%284+%2B-+sqrt%28+16+%2B+20+%29%29%2F%282%29+
:
x+=+%284+%2B-+sqrt%28+36+%29%29%2F%282%29+
:
x+=+%284+%2B-+6+%29%2F2+
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Solution using +6:
x+=+%284+%2B+6+%29%2F2+
:
x+=+10%2F2+
:
x = +5
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Solution using -6:
x+=+%284+-+6+%29%2F2+
:
+x+=+-2%2F2+
:
x = -1
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Learn this and you can do them all the same way!