Answer:
x = 8.5
Step-by-step explanation:
I got this answer by assuming the triangles were congurent, if they are not, the answer may vary.
first, make an equation:
x + 8 = 3x - 9
bring 3x to the other side, by subtracting it
-2x + 8 = -9
Subtract 8
-2x = -17
divide by -2
x = 8.5
Then, just sub x into the formulas
