Answer:
x = 12
Step-by-step explanation:
The given triangle is a right-angled triangle
Sum of angles in a triangle is 180 degrees
The angles in the triangle are:
(2x + 1)°, (5x + 5)°, and 90°
(2x + 1) + (5x + 5) + 90 = 180
2x + 5x + 96 = 180
7x = 180 - 96
7x = 84
x = 84/7
x = 12