Find the size of each of the unknown angles. Help me plz
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Answer:
2a+15 = 125(being alternate angle)
or,2a = 125-15
or,2a = 110
or,a = 110÷2
,a = 55
again,2a+15+b+30=180(Being co-interior angle)
or,2×55+15+b+30=180
or,110+15+30+b=180
or,155+b=180
or,b=180-155
Therfore,b=25