# How do you solve 5x - 12 [x - 2 (20 - x )] * 4 * 16 + [8x - 2x * 5] =4250?

Jul 26, 2015

You isolate $x$ on one side of the equation.

#### Explanation:

Start by getting rid of the parantheses - remember to use PEMDAS to help you with the order of operations.

$5 x - 12 \left[x - 2 \left(20 - x\right)\right] \cdot 4 \cdot 16 + \left(8 x - 2 x \cdot 5\right) = 4250$

$5 x - 12 \left(x - 40 + 2 x\right) \cdot 64 + \left(- 2 x\right) = 4250$

$3 x - 12 \left(3 x - 40\right) \cdot 64 = 4250$

$3 x - 2304 x + 30720 = 4250$

$- 2301 x + 30720 = 4250$

To isolate $x$ on one side of the equation, add $- 30720$ to both side of the equation

$- 2301 x + \textcolor{red}{\cancel{\textcolor{b l a c k}{30720}}} - \textcolor{red}{\cancel{\textcolor{b l a c k}{30720}}} = 4250 - 30720$

$- 2301 x = - 26470$

Finally, divide both sides of the equation by $- 2301$ to get

$\frac{\textcolor{red}{\cancel{\textcolor{b l a c k}{- 2301}}} x}{\textcolor{red}{\cancel{\textcolor{b l a c k}{- 2301}}}} = \frac{- 26470}{- 2301}$

$x = \frac{26470}{2301} \approx \textcolor{g r e e n}{11.5}$