2006-09-14 10:30:43 · 7 answers · asked by nanap1963 2 in Science & Mathematics ➔ Mathematics
To solve for 3 variables, you must have 3 equations.
You solve these in a similar way as you do 2 variable equations: substitution, addition (or elimination) method, or matrices.
2006-09-14 10:34:22 · answer #1 · answered by MsMath 7 · 3⤊ 1⤋
You need to cancel out 1 of the variables then solve for 2 variable equation then plug that value into equation and solve for the other 2
2006-09-14 11:10:11 · answer #2 · answered by Anonymous · 1⤊ 0⤋
If you have an equation with 3 vairables and you are asked to solve the equation for one of those 3, that means that you want to get that one variable by itself on the left side of the equals sign and have everything else on the right side. I can't give you a general description on how to do this since each problem is different.
2006-09-14 10:37:43 · answer #3 · answered by Demiurge42 7 · 1⤊ 0⤋
assumption: equations are linear
step 1: take 2 equations at a time (say A and B and then B and C) and make coefficients of a variable equal and subtract... that variable will vanish
step 2: now u have 2 equations and 2 variables.... solve
eg:
x+y+z = 9 (A)
2x+y+2z = 15 (B)
3x+2y+z = 20 (C)
taking A & B we get
x+z = 6 (D) (by B-A) ... we have eliminated y; do the same for another set of equations now...
taking A & C we get
2x+2y+2z = 18 (2A) and 3x+2y+z = 20 (C)
now (C-2A) yields x-z=2 (E)
using D & E, we can easily solve for x and z
2006-09-14 11:03:12 · answer #4 · answered by m s 3 · 1⤊ 0⤋
you have to come up with 3 different equations! one for each variable!
2006-09-14 10:32:34 · answer #5 · answered by BahamaBlue 2 · 1⤊ 0⤋
you can only solve for one variable at a time ie x= 13p-7(3-k)
2006-09-14 10:39:23 · answer #6 · answered by x1yofuzzy1x 4 · 1⤊ 0⤋
Cramer's rule
Gaussian elimination
Substitution
2006-09-14 10:36:26 · answer #7 · answered by Anonymous · 1⤊ 1⤋