SOLUTION: hello I'm having trouble with this problem Using the Quadratic Formula, which of the following is the solution to the quadratic equation 5x2 + 10x – 5 = 0? a..x=-1-√5,x

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Question 900399: hello I'm having trouble with this problem
Using the Quadratic Formula, which of the following is the solution to the quadratic equation 5x2 + 10x – 5 = 0?
a..x=-1-√5,x=-1+√5
b.x=-1-√2,x=-1+√2
c.x=-1-√201,x=-1+√201-i picked
d.x=-1-√2,x=1+√2
Found 2 solutions by ewatrrr, richwmiller:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi

5x^2 + 10x – 5 = 0  Format a^2 + bx + c

x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

x+=+%28-10+%2B-+sqrt%28+100%2B100+%29%29%2F%2810%29+

x+=+%28-10+%2B-+sqrt%28+200+%29%29%2F%2810%29+

x+=+%28-10+%2B-+sqrt%28+100%2A2%29%29%2F%2810%29+

x+=+%28-10+%2B-+10sqrt%28+2%29%29%2F%2810%29+

x+=+-1+%2B-+sqrt%28+2%29

d.x=-1-√2,x=1+√2

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: Quadratic Formula
Let's use the quadratic formula to solve for x:


Starting with the general quadratic


ax%5E2%2Bbx%2Bc=0


the general solution using the quadratic equation is:


x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29




So lets solve 5%2Ax%5E2%2B10%2Ax-5=0 ( notice a=5, b=10, and c=-5)





x+=+%28-10+%2B-+sqrt%28+%2810%29%5E2-4%2A5%2A-5+%29%29%2F%282%2A5%29 Plug in a=5, b=10, and c=-5




x+=+%28-10+%2B-+sqrt%28+100-4%2A5%2A-5+%29%29%2F%282%2A5%29 Square 10 to get 100




x+=+%28-10+%2B-+sqrt%28+100%2B100+%29%29%2F%282%2A5%29 Multiply -4%2A-5%2A5 to get 100




x+=+%28-10+%2B-+sqrt%28+200+%29%29%2F%282%2A5%29 Combine like terms in the radicand (everything under the square root)




x+=+%28-10+%2B-+10%2Asqrt%282%29%29%2F%282%2A5%29 Simplify the square root (note: If you need help with simplifying the square root, check out this solver)




x+=+%28-10+%2B-+10%2Asqrt%282%29%29%2F10 Multiply 2 and 5 to get 10


So now the expression breaks down into two parts


x+=+%28-10+%2B+10%2Asqrt%282%29%29%2F10 or x+=+%28-10+-+10%2Asqrt%282%29%29%2F10



Now break up the fraction



x=-10%2F10%2B10%2Asqrt%282%29%2F10 or x=-10%2F10-10%2Asqrt%282%29%2F10



Simplify



x=-1%2Bsqrt%282%29 or x=-1-sqrt%282%29



So the solutions are:

x=-1%2Bsqrt%282%29 or x=-1-sqrt%282%29