Question 214166
p=h+40
.75p+1.35h=292.50
.75(h+40)+1.35h=292.50
.75h+30+1.35h=292.50
2.1h=292.50-30
2.1h=262.5
h=262.5/2.1125 
h=125 hamburgers were sold.
p=125+40=165 pieces of pizza were sold.
Proof:
.75*165+1.35*125=292.50
123.75+168.75=292.50
292.50=292.50