Answer:
99x78=7722
123x56=6888
98x172=16856
900x38=34200
Step-by-step explanation:
z=-8
b+3a
MN=AN+AM
AN=0.5*AB
AB=OA+OB=4a+2b
AN=2a+b
AM=OA-OM=4a-3a=a
MN=2a+b+a=3a+b