advance algebra
posted by AD .
find three numbers such that the second is 6 less than 3 times the first , and the third is 2 more than 2/3 of the 2nd.The sum of the three numbers is 172.
use x=1st number
y=second number
z= 3rd number
please help...thanks a lot!!

You have 3 consecutive questions of this type.
Why do you want to use 3 variables, it is much easier to just define one, and the use the given to define the others.
e.g.
let the first number be x
then the 2nd number is 3x6
and the 3rd is (2/3)(3x6) + 2 = 2x 4 + 2 = 2x  2
then x + 3x6 + 2x2 = 172
6x = 180
x = 30
1st = 30
2nd = 3(30)6 = 84
3rd = 58
check: 30+84+58 = 172
try the others using only one variable.