Answer:
The triangle has three angles, A, B, and C, with
A+B=π2,(1)
and
C=2A.(2)
As with all triangles,
A+B+C=π.(3)
Inserting equations (1) and (2) into equation (3) gives
π2+2A=π,(*)
so
A=π4.(4)
Combining equations (1) and (4) gives
B=π4.(5)
Combining equations (3)-(5) gives
C=π.(6)
(All angular units here are radians.)
