Answer:
a = 138
Step-by-step explanation:
< RON = 90 since it is a right angle
RON is formed by 2 angles ROQ and QON
ROQ + QON = 90
48 + QON = 90
QON = 90-42
QON = 42
We know that QOP is a straight line
QOP = 180
QOP is formed by 2 angles QON and NOP
QON + NOP = 180
42+ NOP = 180
NOP = 180-42
NOP =138
a = NOP = 138
