Answer:
x = -9
Step-by-step explanation:
Given the equation:
[tex]\displaystyle{28=-9x-8+5x}[/tex]
First, simplify the like term of x-variable:
[tex]\displaystyle{28=-8-4x}[/tex]
Then add both sides by 8 since we are trying to solve for x, we have to isolate x:
[tex]\displaystyle{28+8=-8+8-4x}\\\\\displaystyle{36=-4x}[/tex]
Finally, divide both sides by -4, without forgetting that dividing positive with negative always result in negative:
[tex]\displaystyle{\dfrac{36}{-4}=\dfrac{-4x}{-4}}\\\\\displaystyle{-9=x}[/tex]
And also, dividing negative with negative is always positive. You can think like this:
And thus, x = -9