math
posted by deedee on .
Can someone please check my work?
Solve using substitution method
1. 3x+2y=12
x=526y
answer:40.8 I am pretty sure that one is wrong.
Solve using elimination method
2. 2r7s=31
7r+2s=24
answer: (230/53,468/53)
3.3x+4y=3
6x+8y=6
answer: No answer. problems eliminate eachother

3(526y) + 2 y = 12
156  18 y + 2 y = 12
16 y = 144
y = 9
x = 52  6(9) = 52  54 = 2 
Thank you Damon!
Can you help me with the formula to solve by elimination? 
3x+2y=12
x=526y multiply everything by 3 on this line
3x+2y=12
3 x = 156  18y
 subtract
0 x + 2y = 12 156 + 18 y
0 =  144 + 16 y
y = 144/16 = 9 again 
2r7s=0
7r+2s=53 
6,174,000,000