Answer:
 32 
Explanation:
 As we know the total degree of a triangle is 180 degrees. 
In this triangle so far we have a 58 degree and 90 degree box since its a right triangle so we have to take: 
 58 + 90 = 148 
After taking 148 we have to subtract the 180 to find the missing number that will help us complete everything: 
 180 - 148 = 32