Answer:
[tex]\large\boxed{x=\dfrac{45}{4}=11\dfrac{1}{4}}[/tex]
Step-by-step explanation:
[tex]-8x=-90\qquad\text{divide both sides by (-8)}\\\\\dfrac{-8x}{-8}=\dfrac{-90}{-8}\\\\x=\dfrac{90}{8}\\\\x=\dfrac{90:2}{8:2}\\\\x=\dfrac{45}{4}\to x=11\dfrac{1}{4}[/tex]