SOLUTION: I am solving a quadratic equation. I think I have done it right, but I am not sure how to write the final answer. Would you please check my work? 5x^2+22=-10x +10x -10

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: I am solving a quadratic equation. I think I have done it right, but I am not sure how to write the final answer. Would you please check my work? 5x^2+22=-10x +10x -10      Log On


   

Question 410826: I am solving a quadratic equation. I think I have done it right, but I am not sure how to write the final answer. Would you please check my work?
5x^2+22=-10x
+10x -10x+10x
5x^2+22+10x=0
a c b
-10+-sqrt((10)^2-4(5)(22)/2(5)
-10+-sqrt(100-(-440))/(10)
-10+-sqrt(500)/(10)
-10+-sqrt(5(100))/(10)
-10+-10sqrt(5)/(10)
1+-sqrt(5)/(1)
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
Not quite. You have a sign error in the following steps:

-10+-sqrt((10)^2-4(5)(22)/2(5)
-10+-sqrt(100-(-440))/(10) <--- should be 100 - 440, not 100 - (-440). Also, 100 - (-440) = 540, not 500.

By the quadratic formula, x+=+%28-10+%2B-+sqrt%28100+-+440%29%29%2F10+=+%28-10+%2B-+sqrt%28-340%29%29%2F10. We can factor 4 out of sqrt%28-340%29 to obtain 2sqrt%28-85%29. This becomes

.

In addition, it is more conventional (and less likely to make a mistake) to write the quadratic as 5x%5E2+%2B+10x+%2B+22 instead of 5x%5E2+%2B+22+%2B+10x.