# Thread: Help needed.

1. ## Help needed.

Please help me to solve these four:

X^2 = 9/16

and

X/6 = 15 + x

and

X^2 - X - 6 = 0

and

2x^2 - 3x = 0

Thank you very much!

2. Originally Posted by Shandy
Please help me to solve these four:
Thank you very much!
X^2 = 9/16
$(\sqrt{x})^2=\sqrt{\frac{9}{16}}$

$x=\frac{3}{4}$
$x= -\frac{3}{4}$ as corrected by earboth

$X/6 = 15 + x$
$\frac{x}{6}*\frac{6}{6}= 6(15 + x)$

$x= 90 +6x$

$x-6x = 90$

$-5x = 90$

$x= -18$

X^2 - X - 6 = 0
$(x+2)(x-3)=0$

$x+2=0 | x-3=0$

$x=-2 |x=3$

2x^2 - 3x = 0

try doing the last one.

3. Originally Posted by Shandy
Please help me to solve these four:

X^2 = 9/16

...
Keep in mind that $\sqrt{x^2} = |x|$

Calculate the square root on both sides of your equation:

$x^2=\dfrac9{16}~\implies~|x|=\dfrac34~\implies~x=-\dfrac34~\vee~x=\dfrac34$

4. forgot that part. thanks