16 us customary cups are in a gallon
Area is width times length
Since you know the area and width you can plug them in
100=5*length
length=20
Is number2 Extend I think
Distribute the 5 to the y and -4 which would be 5y-20= -10 then add 20 on both sides so the 20s will cancel and you’re left with 5y=10 then you divide 5 on both sides do you can get the y by itself and the answer is y=2