SOLUTION: solutions to the problem 16x^2-64=0

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Question 342743: solutions to the problem 16x^2-64=0
Found 2 solutions by jim_thompson5910, stanbon:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

16x%5E2-64=0 Start with the given equation.


Notice that the quadratic 16x%5E2-64 is in the form of Ax%5E2%2BBx%2BC where A=16, B=0, and C=-64


Let's use the quadratic formula to solve for "x":


x+=+%28-B+%2B-+sqrt%28+B%5E2-4AC+%29%29%2F%282A%29 Start with the quadratic formula


x+=+%28%280%29+%2B-+sqrt%28+%280%29%5E2-4%2816%29%28-64%29+%29%29%2F%282%2816%29%29 Plug in A=16, B=0, and C=-64


x+=+%280+%2B-+sqrt%28+0-4%2816%29%28-64%29+%29%29%2F%282%2816%29%29 Square 0 to get 0.


x+=+%280+%2B-+sqrt%28+0--4096+%29%29%2F%282%2816%29%29 Multiply 4%2816%29%28-64%29 to get -4096


x+=+%280+%2B-+sqrt%28+0%2B4096+%29%29%2F%282%2816%29%29 Rewrite sqrt%280--4096%29 as sqrt%280%2B4096%29


x+=+%280+%2B-+sqrt%28+4096+%29%29%2F%282%2816%29%29 Add 0 to 4096 to get 4096


x+=+%280+%2B-+sqrt%28+4096+%29%29%2F%2832%29 Multiply 2 and 16 to get 32.


x+=+%280+%2B-+64%29%2F%2832%29 Take the square root of 4096 to get 64.


x+=+%280+%2B+64%29%2F%2832%29 or x+=+%28-0+-+64%29%2F%2832%29 Break up the expression.


x+=+%2864%29%2F%2832%29 or x+=++%28-64%29%2F%2832%29 Combine like terms.


x+=+2 or x+=+-2 Simplify.


So the solutions are x+=+2 or x+=+-2


If you need more help, email me at jim_thompson5910@hotmail.com

Also, feel free to check out my tutoring website

Jim

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solutions to the problem
16x^2-64=0
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Factor:
16(x^2-4) = 0
Factor:
(x-2)(x+2) = 0
x = 2 or x = -2
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Cheers,
Stan H.
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