Quadratic formula?

Question

The quadratic formula: Solve the quadratic equation by using the quadratic formula. If the
roots are irrational, give the rational approximations to the nearest tenth.
Please, FILL in the blanks!
3x^2 + 4x - 2 = 0
{___, ____}

x^2/3 + 1/2 = (5/6)x

{___,___}

Thanks!

Answer 1

Question 1
x = [- 4 ± √(16 + 24)] / 6
x = [- 4 ± √ 40 ] / 6
x = [- 4 ± 2√10] / 6
x = - 0.7 ± 1.1
Question 2
Reading this as:-
x² / 3 + 1 / 2 = (5/6).x
2x² + 3 = 5x
2x² - 5x + 3 = 0
(2x - 3).(x - 1) = 0
x = 3/2 , x = 1
x = 1.5 , x = 1
OR
x = [5 ± 1] / 4
x = 3/2 ,x = 1 as above.
x = 1.5, x = 1

Answer 2

For an equation ax^2 + bx +c=0
Quadratic formula for solving for x:
x= (-b ± (b^2 - 4*a*c)^(1/2))/2a
the ± signs will give two different answers. Note: if the values in the square root is negative, no answer exists.

So, for the first one, x = (-4 ± (16 - 4*3*(-2))^1/2)/2*3
= (-4 ± (40)^1/2)/6

Hence, x = 0.387(3.dp) and -1.721 (3.dp)

Sorry, I can't figure out the second one... though still trying :P.

Answer 3

x = -b + or - the sqrt of b^2 minus 4ac all over 2a

Answer 4

(.39, -1.72) for the first

i dont quite get the second