SOLUTION: john's age is four less than six times his brother's age and the sum of thier ages is equal to ten.how do you slove this proublem?

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Question 54527: john's age is four less than six times his brother's age and the sum of thier ages is equal to ten.how do you slove this proublem?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Let Johns's age = J; Let his brother's age = B
:
Write an equation for each sentence, (the word "is" usually means =)
:
"John's age is four less than six times his brother's age"
J = (6 * B) - 4
or just write it:
J = (6B - 4)
:
:
" the sum of their ages is equal to ten."
J + B = 10
:
In the 1st equation it says J = (6B-4) so substitute that for J in the 2nd eq:
(6B-4) + B = 10
6B - 4 + B = 10
7B = 10 + 4
7B = 14
B = 14/7
B = 2
:
Find out John's age with the 2nd equation:
J + 2 = 10
J = 10-2
J = 8
:
Check our solution in the 1st equation: 6(2) - 4 does indeed = John's age!