The angle next to the angle 5x is 180 - 5x
All angles sum to 360
(6x - 58) + (2x + 4) + (180 - 5x) = 180
3x + 126 = 180
3x = 54
x = 18
For question 10, sum of angles in pentagon is 540 degrees
x + 105 + 85 + 114 + 126 = 540
x + 430 = 540
x = 110
Hi there! The answer is 15/8.
The general formula for the tangent is

When we fill in the data from the picture, we get the following:
Cole's mistake was that he rounded 555 to the nearest hundred instead of the nearest ten. He should've rounded it to 560 because the tens place is the second number, not the first one.