Solve. For x

1. 3x^2-6=0
2. 1/x (6x^3+5x^2)=21
3. x/2+6=-10/x
4. 2x^2=14x

3 answers

x^2 = 2
x = +/- sqrt 2

2. not sure what is denominator

3. x^2/2 + 6 x + 10 = 0
x^2 + 12 x + 20 = 0
(x+10)(x+2) = 0
x = -10 or x = -2

4. x^2 - 7 x = 0
x (x-7) = 0
x = 0 or x = 7
Thanks damon
Thanks damon but I don't understand what did you on number 3???