Solve. Round results to the nearest thousandth.
5x^2 - 14x + 14 = 0

Question

Solve. Round results to the nearest thousandth. 
5x^2 - 14x + 14 = 0

campbell_st · Answer

well the question will have complex roots.... 

the discriminant is 14^2 - 4 x 5 x 14   = -84

bbb911 · Answer

that what i have but the answers are different

campbell_st · Answer

so the solutions using the general quadratic formula are 

$$x = \frac{14 \pm \sqrt{-84}}{2 \times 5}$$

which becomes 

$$x = \frac{7 \pm i \sqrt{21}}{5}$$

hope that helps

campbell_st · Answer

well if it was - 14 then you will get real solutions...

bbb911 · Answer

ok lemme show you the answers cos im confused

bbb911 · Answer

a. 2.317, 0.483
b. 0.782, -3.582
c. 3.582, -0.782
d. -0.483, -2.317

campbell_st · Answer

well I got answer b when I used the equation 

$$5x^2 - 14x - 14 = 0$$

campbell_st · Answer

you get 

$$x = \frac{14 \pm \sqrt{476}}{10}$$

campbell_st · Answer

well I got the 1st part of b  the 2nd option I had was a postive... not negative... same value...

bbb911 · Answer

oh ok sounds good ill just put that as the answer thank you :D

bbb911 · Answer

i was wonder if you can help me on 3 more questions :)

campbell_st · Answer

I think the equation should read 

$$5x^2 + 14x - 14 = 0$$

if you use that solution I think you get option b

this is definitely the equation that gives b as the answer

looks like a typo

campbell_st · Answer

if you post them I'll look at them

bbb911 · Answer

oh my goodness that is what i was thinking about it was a typo so i wasn't going crazy after all