Posted by HELP me please asap!! on .
PLEASE!!!!i need help on these 4:
*4y=153x
2y=3x+21
*4x=5y14
y=6x9
*5x=4y30
2x=3y=12
*2/3y=10+4x
5x=1/3y8
use linear combinations to solve the system of linear equations
thank you!!!

math 
MathMate,
4y=153x ...(1)
2y=3x+21 ...(2)
Rewrite in standard form:
3x+4y15=0....(1a)
3x2y+21=0....(2a)
Subtract 2a from 1a to get
0x+6y  36 = 0
from which y=6
Add 2(2a) to (1a) to get
9x+0y+27 = 0
from which x = 3
Check:
4y=24, 153x=24 OK
2y=12, 3x+21=12 OK
You can proceed the same way for the remaining problems. Post for answer verification if you wish, but it should not be necessary because a check with the original equations should have been done as in the example.