Respuesta :
Systems of Equations Word Problems
To solve these questions, we can translate key words into operations:
- Difference = subtract
- Twice = double
- Less than = subtract
Solving the Question
We're given:
- Difference of Annie's age and twice Carl's age is 22
- Annie's age is 13 less than 3 times Carl's age
There are two variables given two us: Annie's age and Carl's age.
- Let Annie's age be equal to x.
- Let Carl's age be equal to y.
Translate the given information into two equations:
- Difference of Annie's age and twice Carl's age is 22
⇒ [tex]x-2y=22[/tex]
- Annie's age is 13 less than 3 times Carl's age
⇒ [tex]x=3y-13[/tex]
Now, we can substitute the fist equation into the second one to solve for y:
[tex](3y-13)-2y=22\\3y-13-2y=22\\y-13=22\\y=35[/tex]
Now, substitute y back into the second equation to solve for x:
[tex]x=3y-13\\x=3(35)-13\\x=105-13\\x=92[/tex]
Answer
Therefore, Grandma Annie is 92 years old.