Answer:
   45°
Step-by-step explanation:
The acute angles of a right triangle are complementary. The base angles of an isosceles triangle are congruent. If x is the measure of the base angles, this requires ...
   x = 90-x . . . . . the base angle is congruent to the other base angle
   2x = 90 . . . . . add x
   x = 90/2 = 45 . . . . divide by 2
The measure of a base angle of an isosceles right triangle is 45°.
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It can be useful to remember this fact.
 
        
             
        
        
        
Answer:
A. 22.5 cm, 30 cm, and 37.5 cm
Step-by-step explanation:
If three sides of a triangle are in the ratio 3:4:5, then the lengths of the sides are 3x cm, 4x cm and 5x cm.
The preimeter of the triangle is the sum of the lengths of all sides, thus

So, the lengths of the triangle's sides are

 
        
                    
             
        
        
        
Answer:
1.) SSS
Step-by-step explanation: