Answer:
14
Step-by-step explanation:
By applying the vertical angle theorem to 5x + 3, using same-side exterior angle theorem, we can find that:
(7x + 9) + (5x + 3) = 180
Now to find x, we can just solve for x in the equation we found.
(7x + 9) + (5x + 3) = 180
Combine like terms.
12x + 12 = 180
Subtract 12 from both sides.
12x = 168
Divide both sides by 12.
x = 14
So the value of x would be 14.
I hope you find my answer and explanation to be helpful. Happy studying.