Sunday
March 29, 2015

Homework Help: Math

Posted by Me on Friday, April 9, 2010 at 3:15pm.

Help pls! I just need to set the equations only, I can do the rest. The qu. Is:
The sum of three numbers is 15. The sum of the first, the second, and twice the third is 20. The sum of the first, twice the second, and three times the third is 27.
This is what I did:
1st # = x
2nd # = y
3rs # = z
so
x+y+z=15
x+y+2z=20
x+2y+3z=27
then solved by elimination of z, and finally got (16,10,-1)
where is my mistake?
Where is my mistake?

Answer this Question

First Name:
School Subject:
Answer:

Related Questions

math - Hi, for the question, "the sum of two numbers is equal to a third number(...
Math 8th grade - I NEED THESE IN ALGEBRAIC EXPRESSION!! The larger of two sums ...
algebra - Twice the first number is eleven more than the sum of the other two ...
Math (Probability) - I've worked out the first part of the question, just need ...
algebra - Five times the smallest of three consecutive odd integers is ten more ...
Math riddle - nine odd numbers have a sum of 243.find the sum of the first and ...
algebra & trigonometry - The sum of three whole numbers is 7. The second number...
algebra & trigonometry - The sum of three whole numbers is 7. The second number...
Algebra - three numbers are such that the second is the difference of three ...
Math riddle - nine odd numbers have a sum of 243.find the sum of the first and ...

Members