How do you work out:
5u-v+2w=25
3u+2v-3w=16
2u-v+w=9
I have tried loads of times already and can't get the right answer.
How do you work out:
1--5u-v+2w=25
2--3u+2v-3w=16
3--2u-v+w=9
Multiply (1) by 2 and add to (1) giving you an equation in u and w.
Multiply (3) by 2 and add to (2) giving you another equation in u and w.
Multiply one of them by whatever makes the coefficients of u or w equal to one another.
Add, or subtract, whichever eliminates one of the variables and you are left with one equation in one unknown to solve.