y1= -3/8x+7
-39x+24y= -216
show work
2007-09-04 09:49:59 · 6 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
Eliminate y from the second equation to solve for x.
Then vice versa for the first equation.
y = -3/8x + 7
so
24y = 24(-3/8x+7) = -9x + 168
so
-39x + 24y = -216
is the same as
-39x -9x + 168 = -216
move the variables to the left hand side
-48x = -384
so
48x = 384
or
x = 8
Now we can use this result to find y
y = -3/8x + 7
y = -3/8(8) + 7
y = -3 + 7
y = 4
Check the answers by subbing them back into the equation
4 = -3 + 7 is true
-312 + 96 = -216 is also true
2007-09-04 10:02:50 · answer #1 · answered by tekn33k 3 · 0⤊ 0⤋
y = -3/8x + 7
3/8x + y = 7 (x 8)
3x + 8y = 56 ( to eliminate 'x' multiply by 13)
39x + 104y = 728
-39x + 24y = -216
Add these two equations
128y = 512 (divide by 128)
y = 4 substitute in for 'y'
-39x + 24(4) = -216
-39x + 96 = -216
-39x = -216 - 96
-39x = -312 (divide by -39)
x = 8
2007-09-04 17:01:22 · answer #2 · answered by lenpol7 7 · 0⤊ 0⤋
This is not the right answer lol
-39x + 24(3/8x+7)= -216
-39x + 9x + 168= -216
-30x= -168-216
-30x= -384
x = 12 4/5
y= -3/8(12 4/5) + 7
y= -4.8+ 7
y=2.2
-39(12.8) + 24(2.2)= -216
-499.2 + 52.8
2007-09-04 17:02:11 · answer #3 · answered by Prisoner of Grace 3 · 0⤊ 0⤋
-39x + 24 * (-3/8x+7) = -216
-39x -9x + 168 = -216
-48x = -364
x = 8
2007-09-04 16:55:33 · answer #4 · answered by Anonymous · 1⤊ 0⤋
Im confused, i don;t think you can solve by elimination here, and whats y1? a typo or is it y(sub 1)
srry
repost and ill try to do it
2007-09-04 16:54:18 · answer #5 · answered by bassboy22 3 · 0⤊ 1⤋
elemintation?
and what would that be ? :-)
2007-09-04 16:54:56 · answer #6 · answered by Anonymous · 0⤊ 1⤋