Answer:
[tex]x = \frac{46}{3} [/tex]
Step-by-step explanation:
A straight angle is equal to 180° degrees. Since both 9x +4 and 3x -18 is supplementary then I can make this claim below
[tex](9x + 4 ) + (3x - 8) = 180[/tex]
All we have to do now is to solve for x
[tex](9x + 4) + (3x - 8) = 180 \\ 9x + 4+ 3x - 8 = 180 \\ 12x - 4 = 180 \\ 12x = 184 \\ x = \frac{184}{12} \\ x = \frac{46}{3} [/tex]
