Answer:
33.7°
Explanation:
We know that both small triangles are right triangles, but we don't know that the large triangle is a right triangle.
1. Find the altitude of the large triangle.
a² + b² = c²
2.5² + b² = 5²
b² = 25 - 6.25
b² = 18.75
b = √18.75
The altitude of the large triangle is the opposite leg to angle x in the left small triangle. The adjacent leg to angle x is 6.5 cm.
tan x = opp/adj
tan x = √18.75/6.5
tan x = 0.6661733
x = tan^-1 0.6661733
x = 33.7
Answer: 33.7°