3x-2y=1 and 2x+y=-4

3 answers

Multiply second equation by 2.

4x + 2y = -8

3x - 2y = 1

Add the two equations to solve for x. Insert x into one of the equations to solve for y.
I assume you are solving?

from the 2nd:
y = -2x-4
sub into the first
3x - 2(-2x - 4) = 1
3x + 4x + 8 = 1
7x = -7
x = -1
back into y = -2x - 4
y = -2(-1) - 4 = -2

x = -1 , y = -2
Rearange your equations.

3 x - 2 y = 1 Multiply both sides by 2

6 x - 4 y = 2

2x + y = - 4 Multiply both sides by 3

6 x + 3 y = - 12

6 x - 4 y = 2
-
6 x + 3 y = - 12
______________

6 x - 6 x - 4 y - 3 y = 2 - ( - 12 )

0 - 7 y = 2 + 12

- 7 y = 14 Divide both sides by - 7

y = 14 / - 7

y = - 2

Put this value into equation:

3 x - 2 y = 1

3 x - 2 * ( - 2 ) = 1

3 x + 4 = 1 Subtract 4 to both sides

3 x + 4 - 4 = 1 - 4

3 x = - 3 Divide both sides by 3

x = - 3 / 3

x = - 1

The solutions are x = - 1 and y = - 2