please help me on number 4
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Answer:
143degrees
Step-by-step explanation:
sum of angles of a triangle =180degrees
let the third unknown angle be x
99+37+x=180
136+x=180
x=180-136
x=44
the sum of two opposite interior angles is equal to the exterior angle
44+99=<PQR
<PQR=143 degrees.
OR
the sum of angles on a straight line is 180 degrees
<PQR+37=180
<PQR=180-37
<PQR=143