Question

Solve the system of equations by elimination
3x+4y=31
2x-4y=-6

Answer 1

3x + 4y = 31
2x - 4y = -6

*The +4 and -4 in the center of the equation cancel out because 4-4 = 0*

3x = 31
2x = -6
------------

*add like terms*

3x + 2x = 5x

31 - 6 = 25

So now you should have this written on your paper ... > 5x = 25

*Divide by 5 on each side*

5x = 25
_ _
5 5

x = 5

Answer 2

x = 5 and y = 4

Explanation:

In elimination method we solve a system of two variable equations by eliminating one variable by operating the equations.

Given system of equations,

3x + 4y = 31 ------(1)

2x - 4y = -6 --------(2),

Equation (1) + equation (2),

3x + 2x = 31 - 6

5x = 25

x = 5

From equation (1),

3(5) + 4y = 31

15 + 4y = 31

4y = 16

y = 4

Hence, the solution of the given equations is, x = 5, y = 4