Answer:
a=30
b=60
c=105
Explanation:
We know a=30 because 30 and a are the same
The middle forms a triangle and triangles are equal to 180
The box indicates that the angle is 90 degrees
180=a+b+90
180=30+90+b
b=60
Angle c is supplementary to 75 so it must equal 180
180=c+75
c=105
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