-3x + y = 7
5x + 2y = 3
This is solved by SIMULTANEOUS Eq'ns.
Arbitrarily decide which letter to eliminate. In this case 'y' .
To do this multiply the top eq'n by '-2'
Hence
(+)6x - 2y = -14 ( Notice the double negative multiple becomes plus(+).
5x + 2y = 3
Add the two eq'ns
11x = -11 (Notice the 'y' has been eliminated).
x = -1
When x = -1
-3(-1) + y = 7
3 + y = 7
y = 4
Hence the solution in ( x,y) form is ( -1,4).
A system of equations? Try elimination.
- 2(-3X + Y = 7)
5X + 2Y = 3
6X - 2Y = - 14
5X + 2Y = 3
--------------------------add
11X = - 11
X = - 1
------------Put back in equation to solve for Y
- 3(-1) + Y = 7
3 + Y = 7
Y = 4
-------------check both equations
- 3(-1) + 4 = 7
3 + 4 = 7
top checks
5(-1) + 2(4) = 3
- 5 + 8 = 3
both equations check and the system is consistent
3x+2y=6 2y=-3x+6 y=-1.5x+3
3x-2y=6 -2y=-3x+6 y=1.5x-3
3x + 2y = 7
3x-2y = 5 -2y = -3x+5 y = 1.5x-2.5 in slope intercept form
y=16 x= -4
3x + 2y = 12 ie 2y = 12 - 3x so y = 6 - 3x/2
3x+2y=6 2y=-3x+6 y=-1.5x+3
2y-3x=4
3x-2y=6 -2y=-3x+6 y=1.5x-3
-3x + 2y = 9 2y = 3x + 9y = 1,5x + 4,5
You cannot solve one linear equation in two unknown variables.
3x + 2y = 7
3x-2y = 5 -2y = -3x+5 y = 1.5x-2.5 in slope intercept form
y=16 x= -4
4x-y=2, thereforey=4x-2sub y into 3x+2y=6...3x+8x-4=611x=10x=10/11
(2, -1)
Standard form is: y = Mx + b so you must solve for y 3x = 2y + 7 3x - 7 = 2y 2y = 3x - 7 y = ( 3 / 2 )x - ( 7 / 2 )