Let the age of the lizard be X
then the cats age would be 3X ( three times the lizards age)
A) write the formula:
X + 3X = 16
B) Solve:
x +3x = 16
Combine like terms:
4x = 16
Divide both sides by 4:
x = 4
Lizard age = 4
Cats age = 12
The lizards age is 4 and the cats age would be 3 times 4 which is 12.