Question

"The sum of Lisa and Chris’s age is 64. Chris is four more than twice as old as Lisa. (Let L represent Lisa's age and C represent Chris's age.)

Part A: Set up a system of equations to determine their ages. __+__=_____=__+__
Part B: How old is Lisa and how old is Chris?
Lisa is ____ years old.
Chris is ____ years old."

Answer 1

To set up a system of equations, the sum of Lisa and Chris's age is 64, and Chris is four more than twice as old as Lisa. By substituting and solving the equations, we find that Lisa is 20 years old and Chris is 44 years old.

Step-by-step explanation:

To set up a system of equations, we can let L represent Lisa's age and C represent Chris's age. We are given two pieces of information:

1. The sum of Lisa and Chris's age is 64, so we have the equation L + C = 64
2. Chris is four more than twice as old as Lisa, so we have the equation C = 2L + 4

Now we can solve this system of equations:

1. Substitute the value of C from equation 2 into equation 1: L + (2L + 4) = 64
2. Combine like terms: 3L + 4 = 64
3. Subtract 4 from both sides: 3L = 60
4. Divide both sides by 3: L = 20
5. Substitute the value of L into equation 2 to find C: C = 2(20) + 4 = 44

Lisa is 20 years old and Chris is 44 years old.