system of equations 2x + 3y = -3 and x + 2y =2

Question

2x + 3y = -3  and  x + 2y =2.

Answer 1

Elimination method :

The equations are

2x + 3y = -3    ------------>(1)

x + 2y = 2       ------------>(2)

Multiply to 2 to (2).

2x + 4y = 4  ------------>(3)

Subtract (1) from (3).

2x + 4y = 4

2x + 3y = -3
-     -.       +

__________

y = 7

=>y = 7.

Substitute the values y = 7 in (1).

2x + 3(7) = -3

2x +21 = -3

2x = - 3 - 21 = -24

2x = -24

=>x = - 12.

The solution of the system is x = - 12 and y = 7.