The measures of the angle of a triangle are shown on the figure below. Solve for X.

Internal angles sum: 180(sides-2) = 180
5x = 180 - (48 + 90 + 17)
x = 25/5
x = 5
answer: 5
proof:
(90 + 48) + (5(5)+17) = 180
Answer:
x=5
Step-by-step explanation:
We know that a triangle consists of 180°. So to start, you take the two given angles and add them together. 48+90=138.
Now you subtract the 138 from the total of 180 to get the degrees of the remaining angle. 180-138=42°.
Now set the unknown angle equal to 42. (5x+17) = 42
Subtract 17from both sides to get 5x=25
Divide 5 from both sides to get x=5