# How do you solve -100.47= - 7.3( x + 7.1) - 7.9x?

Jan 21, 2018

$x = 3.2$

#### Explanation:

Multiply the bracket(s) to get rid of the brackets as this in the first step in BIDMAS/BODMAS.

color(orange)(-7.3 xx x=-7.3x

color(blue)(-7.3 xx 7.1=-51.83

This gives us $\textcolor{b l u e}{- 100.47} = \textcolor{\mathmr{and} a n \ge}{- 7.3 x} \textcolor{b l u e}{- 51.83} \textcolor{\mathmr{and} a n \ge}{- 7.9 x}$

Collect like terms on each side if possible, in this instance only the right...

color(orange)(-7.3x + -7.9x=-15.2x

This therefore leaves us with:

=> $\textcolor{b l u e}{- 100.47} = \textcolor{\mathmr{and} a n \ge}{- 15.2 x} \textcolor{b l u e}{- 51.83}$

We want $x$ on its own so therefore we do the opposite of color(blue)(-51.83 which is adding color(blue)(51.83 to both sides, as you have to add to both sides of the equation...

$\textcolor{b l u e}{- 100.47} = \textcolor{\mathmr{and} a n \ge}{- 15.2 x} \textcolor{b l u e}{- 51.83}$

=> color(blue)(-48.64)=color(orange)(-15.2x) color(Blue)((+51.83)

Therefore to solve for $x$, we divide the total over how many $x ' s$ we have which goes to...

color(red)(x=-48.64/15.2

As $- 1 \times - 1 = 1$

color(red)(x=48.64/15.2=3.2

Round if necessary, But in this case it's not, so leave it as:

=> $\textcolor{red}{x = 3.2}$