Question

Quadratic Formula: 5 x^2 +x=5

Answer 1

is it just -1 +- the square root of 101/10?

Answer 2

5x^2+x-5=0
ax^2+bx+c=0 then \[x=-b \pm \sqrt{b^2 -4ac} \div \]

Answer 3

Rewrite: \[5x^2+x-5=0\]

Quadratic formula: \[x=(-b \pm \sqrt{b^2-4ac)})/2\]

So x = (1/2)(-1 +/- sqrt(1-4times1times(-5)) = (1/2)(-1+/- sqrt21)

Answer 4

Yeah i get that but what after that??

Answer 5

div 2a

Answer 6

Yes i know thats too far into decimals to work with

Answer 7

x=-1/2 +/- (1/2)sqrt21=-0.5+/- 2.29 (from calculator)

x= -2.79 or +1.79

Answer 8

yes right

Answer 9

Something's wrong. These solutions don't satisfy the original equation. Back soon.

Answer 10

I forgot to divide by 2a = 10

Answer 11

I know thats what im saying

Answer 12

So sorry - carelessness on my part. Here we go again:

\[x=(-1\pm \sqrt{1-4\times5\times(-5)})/10\]

\[x=(-1\pm \sqrt{101})\div10\]

x = (-1 +/- 10.0499)/10

x = -1.10499 or 0.90499

Answer 13

Still not right!

Answer 14

guyc, I got the same answer:
\[\frac{-1 \pm \sqrt{101}}{10}\] Now the square root of 101 does not simplify since 101 is prime, so this is a final answer.

Answer 15

Yes, I agree with cruffo. Incidentally, my decimal answers do in fact satisfy the original equation. I do hope I didn't confuse you with my ramblings!