SOLUTION: J is 3 years older than K. If you square K's age and add twice J's age, the result is 69. What are their ages?

Algebra ->  Customizable Word Problem Solvers  -> Age -> SOLUTION: J is 3 years older than K. If you square K's age and add twice J's age, the result is 69. What are their ages?      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 1119680: J is 3 years older than K. If you square K's age and add twice J's age, the result is 69. What are their ages?
Found 3 solutions by Tatiana_Stebko, Alan3354, Shin123:
Answer by Tatiana_Stebko(1539) About Me  (Show Source):
You can put this solution on YOUR website!
Let K be x years old, then J be %28x%2B3%29 years old,.
If you square K's age %28x%5E2%29 and add twice J's age 2%2A%28x%2B3%29, the result is x%5E2%2B2%2A%28x%2B3%29 equal to 69
x%5E2%2B2%2A%28x%2B3%29=69
x%5E2%2B2x%2B6-69=0
x%5E2%2B2x-63=0
%28x-7%29%28x%2B9%29=0
x-7=0 or x%2B9=0
x=7 or x=-9 - it's an extraneous root (since it's negative)
K is 7+ years old and J is 7%2B3=10 years old

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
J is 3 years older than K. If you square K's age and add twice J's age, the result is 69. What are their ages?
---------
K = J-3
(J-3)^2 + 2J = 69
etc

Answer by Shin123(626) About Me  (Show Source):
You can put this solution on YOUR website!
K is x years old and J is x%2B3 years old. x%5E2%2B2%28x%2B3%29=69
x%5E2%2B2x%2B6-69=0
x%5E2%2B2x-63=0
%28x-7%29%28x%2B9%29=0
highlight%28x=7%29 or x=-9
7%2B3=highlight%2810%29 K is 7 and J is 10.