2006-09-23 00:02:34 · 11 answers · asked by double B 2 in Science & Mathematics ➔ Mathematics
5x-6y=13 & 3x+6y= -5
5x-6y+3x+6y=13 -5
8x = 8
x = 1
6y = -5-3x = -5-3 = -8
y = -8/6 = -4/3 ~ -1.333333
____________
x = 1
y = -4/3
2006-09-23 00:05:34 · answer #1 · answered by Anonymous · 0⤊ 0⤋
5x + 6y = 13 - - - - - - - - -Equation 1
3x - 6y = - 5 - - - - - - - - - Equation 2
8x = 8
8x/8 = 8/8
x = 1
The solution set is { 1 } for x
Insert the x value into equation 1
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Solving for y
5x - 6y = 13
5(1) - 6y = 13
5 - 6y = 13
5 - 6y - 5 = 13 - 5
- 6y = 8
- 6y/-6 = 8/-6
y = - 8/6
y = - 4/3
The solution set is { - 4/3} for y
Insert the y value into equation 1
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Check
5x - 6y = 13
5(1) - 6(- 4/3) = 13
5 + 24/3 = 13
5 + 8 = 13
13 = 13
- - - - - - - - - - - - - - - - - -
3x + 6y = - 5
3(1) + 6(-4/3) = - 5
3 -24/3 = - 5
3 - 8 = - 5
-5 = - 5
- - - - - - - - - - - - - - - - - - - - - - - - - - - -
The solution set is { 1, - 4/3 }
2006-09-23 10:47:50 · answer #2 · answered by SAMUEL D 7 · 0⤊ 0⤋
Adding both the equations:
5x - 6 y = 13
(+) 3x + 6y = -5
Canceling -6y and +6y, we get:
8x=8
or, x = 1
Now putting x=1 in equation (1), we get:
5*1 - 6y = 13
or,
-6y = 13 - 5
or,
y = 8/-6 = -4/3
Thus,
solution set {1,-4/3}
2006-09-23 07:11:13 · answer #3 · answered by Anonymous · 0⤊ 0⤋
5x - 6y = 13
3x + 6y = -5
if we add these to equations then we get
(5x+3x) + (-6y + 6y) = 13 + -5
8x + 0 = 13 - 5
8x = 8
x = 1
if we sustitute x in any of the equations with 1 we will get the value of y
5.x - 6.y = 13
5.1 -6.y= 13
we shall move -6y to the other side of ( = ) while changing its sigh from - to +
and move 13 the oppsite way while changing its sigh from + to -
therefore
5 - 13 = 6y
-8 = 6y
-8/6 = y
y = - 1.33( minus one and a third of a one)
2006-09-23 07:16:33 · answer #4 · answered by washiko 2 · 0⤊ 0⤋
5x-6y=13
3x+6y= -5
Add the two equation:
8x=8
x=1
Substitute x=1 to any of the equation:
5x-6y=13
5-6y=13
-6y=8
y= -4/3
Ans: x=1, y= -4/3
2006-09-23 08:06:42 · answer #5 · answered by Lin 2 · 0⤊ 0⤋
5x - 6y = 13
3x + 6y = -5
8x = 8
x = 1
5(1) - 6y = 13
5 - 6y = 13
-6y = 8
y = (-4/3)
x = 1
y = (-4/3)
2006-09-23 09:49:24 · answer #6 · answered by Sherman81 6 · 0⤊ 0⤋
for elimination method we eliminate one variable from the given equation
from frist eq. we have
5x-6y=13
ie 5x=13+6y
ie x=(13+6y)/5
now put this value of x in the second equation to get
3((13 + 6y)/5) +6y = -5
now from above equation solve for the value of x
and then put back the value of x in any equation the get the value of y
2006-09-23 07:12:48 · answer #7 · answered by nishu 1 · 0⤊ 1⤋
5x - 6y = 13 eq.1
3x - 6y = -5 eq.2
2x - 0y = 18 Subract
x = 9
Therefore: 5*9 - 6y = 13
6y = 13 - 45
6y = -32
y = -32/6
2006-09-23 07:10:45 · answer #8 · answered by arunprasanth7 1 · 0⤊ 2⤋
5x-6y+3x+6y=13-5
8x=8
x=1
5*1-6y=13
6y=-8
y=-4/3
2006-09-23 07:13:07 · answer #9 · answered by marjan m 3 · 0⤊ 0⤋
6y+3x=-5
6y-5x=-13
8x=8
x=1
solve for y in 5x-6y=13
5-6y=13
5-13=-6y
-8=-6y
8=6y
So:
x=1
y=8/6, or 1.33 recurring...
2006-09-23 07:08:47 · answer #10 · answered by Nene 3 · 0⤊ 2⤋