write each equation in slope-intercept form.
-3x+2y=8
8x-3y=-9
if you get the answer then please tell me step by step how you got it and i would like steps to slove every equation that is like this. thank you!!!
2006-11-09 10:06:12 · 6 answers · asked by Michelle N 2 in Science & Mathematics ➔ Mathematics
(1) -3x+2y=8 multiply by 3 (1a) -9x+6y=24
(2) 8x-3y=-9 multiply by 2 (2a) 16x-6y=-18
add 1a & 1b 7x=6
x=6/7
substitute int (1)
-3(6/7)+2y=8
-18/7+2y=8
2y=56/7+18/7=74/7
y=37/7
check by substituring into (2)
8*(6/7)-3(37/7)=-9
48/7-111/7=-9
-63/7=9
-9=-9
2006-11-09 10:13:19 · answer #1 · answered by yupchagee 7 · 15⤊ 0⤋
Slope intercept form is y = mx + b, so you need to put every equation in that form.
Look at the first one: The -3x needs to move to the right of the equal sign, giving you 2y = 3x + 8. Now you need to isolate the y by dividing by 2.
You get y = 3/2 x + 4.
Now you try the next one.
2006-11-09 10:17:22 · answer #2 · answered by tlf 3 · 0⤊ 0⤋
-3x + 2y = 8
i.e.,
2y = 3x + 8 or y = (3/2)x + 8
8x -3y = 9
i.e.,
3y = 8x +9 or y = (8/3) x +9
2006-11-09 10:14:00 · answer #3 · answered by curious 4 · 0⤊ 0⤋
1. -3x+2y=8
move x to other side by adding 3x to both sides
now, 2y = 8 +3x
now divide both sides by 2 so that left side only has one y
so, y = 4 +3x/2
2. 8x-3y=-9
move x to other side by subtracting 8x
now -3y = -9 -8x
get rid of minus on left by multiplying both sides by -1
so 3y = 9 + 8x
now divide both sides by 3 to get one y
so y = 9/3 + 8x/3
or y = 3 + 8x/3
You can do the same process to solve for x
2006-11-09 10:15:00 · answer #4 · answered by ignoramus 7 · 0⤊ 0⤋
Slope intercept form is y=mx + b. y is your y, of course, x is your x term, m is the number before the x, and b is your lone number.
y=(3/2)x + 4
y=(8/3)x +3
The parenthesis are just there to show that those are fractions...
2006-11-09 10:15:42 · answer #5 · answered by Shaun 4 · 0⤊ 0⤋
-3x+2y=8
8x-3y=9
find what is common in either x or y
+2y and -3y have 6 in common
for 2y = 6/2 = 3
for -3y = 6/-3 = -2
-3x(3)+2y(3)=8(3)
8x(-2)-3y(-2)=9(-2)
so
-9x+6y=24
minus
-16x+6y=-18
so:
-9x-(16x)=-25x
6y-6y=0
24-18=6
then:
-25x=6
x=6/-25
x=-0.24
then use any of the equation
-3x+2y=8 or 8x-3y=9
I used -3x+2y=8
x= -0.24
-3(-0.24)+2y=8
0.72+2y=8
8-0.72=2y
7.28=2y
y=7.28/2
y=3.64
then use either of this equation to check if x and y are correct
-9x+6y=24 or 16x-6y=18
I used -9x+6y=24
_9(-0.24)+6(3.64)=24
2.16+21.84=24
24=24
Your problem solved
2006-11-09 10:35:34 · answer #6 · answered by ron 2 · 0⤊ 0⤋