Start with adding 2 both sides and then multiply by 4.
Multiply by 4 both the sides.
Arrange them in a linear equation and then work out the age.
Multiply by 5 both the sides.
First add 20 both the sides and then divide both the sides by 8.
Think about the relation between the integers using variables.
Put them in an equation with one variable and then work out.
Change the conditions given into linear equation and then work out.