SOLUTION: 7x^2-2=0 using quadratic formula. I am confused because there is no b

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Question 336283: 7x^2-2=0 using quadratic formula. I am confused because there is no b
Found 2 solutions by kshlak, jim_thompson5910:
Answer by kshlak(4) About Me  (Show Source):
You can put this solution on YOUR website!
b=0
7x^2 + 0x -2 =0

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
7x%5E2-2=0+ can be written as 7x%5E2%2B0x-2=0.


7x%5E2%2B0x-2=0 Start with the given equation.


Notice that the quadratic 7x%5E2%2B0x-2 is in the form of Ax%5E2%2BBx%2BC where A=7, B=0, and C=-2


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%287%29%28-2%29+%29%29%2F%282%287%29%29 Plug in A=7, B=0, and C=-2


x+=+%280+%2B-+sqrt%28+0-4%287%29%28-2%29+%29%29%2F%282%287%29%29 Square 0 to get 0.


x+=+%280+%2B-+sqrt%28+0--56+%29%29%2F%282%287%29%29 Multiply 4%287%29%28-2%29 to get -56


x+=+%280+%2B-+sqrt%28+0%2B56+%29%29%2F%282%287%29%29 Rewrite sqrt%280--56%29 as sqrt%280%2B56%29


x+=+%280+%2B-+sqrt%28+56+%29%29%2F%282%287%29%29 Add 0 to 56 to get 56


x+=+%280+%2B-+sqrt%28+56+%29%29%2F%2814%29 Multiply 2 and 7 to get 14.


x+=+%280+%2B-+2%2Asqrt%2814%29%29%2F%2814%29 Simplify the square root (note: If you need help with simplifying square roots, check out this solver)


x+=+%280%2B2%2Asqrt%2814%29%29%2F%2814%29 or x+=+%280-2%2Asqrt%2814%29%29%2F%2814%29 Break up the expression.


x+=+%28sqrt%2814%29%29%2F%287%29 or x+=+-%28sqrt%2814%29%29%2F%287%29 Reduce and simplify.


So the solutions are x+=+%28sqrt%2814%29%29%2F%287%29 or x+=+-%28sqrt%2814%29%29%2F%287%29


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

Also, feel free to check out my website.

Jim