Myapinky654: The zookeeper has a group of crocodiles and emus. ther are a total of 80 legs ang 32 heads. how many emus are there?
equations:
Myapinky654: ther are a total of 32 heads
croc + emu = 32
Myapinky654: ther are a total of 80 legs
croc*4+emu*2 =80
[input]solve( croc + emu = 32, croc*4+emu*2 =80 )[/input]
solve first equation for variable "croc":
croc + emu = 32 <=> croc = 32-emu
insert first equation solved for croc into second equation:
croc*4+emu*2 =80 <=> ( 32-emu)*4+emu*2=80 <=> 32*4-emu*4+emu*2=80 <=> 128+emu*(-4+2)=80 <=> emu*(-2)=80-128 <=> emu*2 = 48 <=> emu = 48/2 <=> emu = 24
+3146 
