The measure of the angle m∠STU is 42 degrees
Find the diagram to the image attached below:
Since the side RS = RU, this shows that:
m∠RTS = m∠RTU
Given the following parameters
m∠RTS = 5w - 69°
m∠RTU = w + 3°
Equating both expressions
5w - 69° = w + 3
5w - w = 3 + 69
4w = 72
w = 72/4
w = 18
Get the measure of m∠STU
m∠STU = m∠RTS + m∠RTU
m∠STU = 5w - 69 + w + 3
m∠STU = 6w - 66
m∠STU = 6(18) - 66
m∠STU = 42 degrees
Hence the measure of the angle m∠STU is 42 degrees