Some people use this rule to work out how many hours' sleep each night
young children need.
tract the child's age in years from 30,
ten divide the result by 2
Sanjay is 8 years old.
Use the rule to work out how many
hours' sleep he needs.

or

step-by-step explanation:

we need to solve for 'x' the following equation:  

we have that:

⇒

⇒ ⇒

factorizing, we get that:

  ⇒

then, the solutions are: or

nothing extraneous has been found!

i dont know the answer but here's a picture of a dog