please answer A and B, with steps if you can you don’t need to but that would be great thank you

Answer:
[tex]x=5.5[/tex]
[tex](3x + 4) = 20.5[/tex]
Step-by-step explanation:
180 = Inside of shape
[tex]180-(89+51)=40[/tex]
[tex]40=(5x-8)+(3x+4)[/tex]
[tex]40=8x-4[/tex]
[tex]40 + 4 = 8x + 4 - 4[/tex]
[tex]44=8x[/tex]
[tex]\frac{44}{8} = \frac{8x}{8}[/tex]
[tex]5.5 = x[/tex]