Answer:
x = 5
Explanation:
Angles on a straight line add up to 180, so add up the angles and equate to 180:
9x + 85 + 10x = 180
Now we can solve for x by simplifying further:
19x + 85 = 180
Subtract 85 on both sides:
19x + 85 - 85 = 180 - 85
19x = 95
Divide 19 on both sides which cancels out the 19 on the left:
x = 95/19 = 5