Answer
9 years watching TV. 28 years spent sleeping.
Work Step by Step
Let $x$ be the number of years spent watching TV.
The number of years spent sleeping is then $x+19$.
The total number of years sleeping and watching TV is 37, so
$x+x+19=37$
Combine like terms.
$2x+19=37$
Use the addition property of equality to subtract 19 from both sides of the equation.
$2x+19-19=37-19$
Combine like terms.
$2x=18$
Use the multiplication property of equality to divide both sides of the equation by 2.
$2x\div2=18\div2$
Simplify.
$x=9$
9 years are spent watching TV.
$x+19=9+19=28$ years are spent sleeping.