SOLUTION: Hi my name is Andrew, and I need help with the following 5 problems my help me with 15 but the last five are giving us trouble. Modeling with Systems of equations Directions: for

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Question 568845: Hi my name is Andrew, and I need help with the following 5 problems my help me with 15 but the last five are giving us trouble.
Modeling with Systems of equations Directions: for the following identify what the variables represent, write a system of equations that Models the problem and solve the system and then write a sentence interpreting your answer.
1. Mr. King is 4 times as old as his daughter. Four years ago he was 6 times as old as his daughter was then. Find each of their ages.
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
Let K and d be the ages of Mr. King and his daughter, respectively. Then,

K = 4d

Four years ago, Mr. King was K-4 years old and his daughter was d-4 years old. Also, we have

K-4 = 6(d-4)

So now we have a system of two equations. We can replace K with 4d to obtain

4d-4 = 6(d-4) = 6d-24

You should get d = 10. Since K = 4d, K = 40.