pls help

 

A straight line is 180^o so AGB is 180^o 

 

CGB is 90^o because that's what a right angle is 

 

CGE is 15^o because it is posited

 

Therefore EGB is 90^o – 15^o  =  75^o  

 

AGF is the same as EGB because they're "opposite angles" (google that term)  

 

Therefore AGF aka X = 75^o    

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