Answer:
19
Step-by-step explanation:
Three angles have to equal 90.
54+17=71
90-71= 19
19 is the the third angle.
The measure of the third angle is 109 degrees
The sum of angles in a triangle is 180 degrees
From the information given;
x is the third angle
Simplify
71 + x = 180
x = 180 - 71
x = 109 degrees
Hence the measure of the third angle is 109 degrees
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