How to do these simultaneous equations by elimination technique

1st

5x-2y=6
3x+2y=26

2nd

3x+2y=11
x+2y=1

3rd

2x+3y=12
x+4y=11

THE TRICK IS TO MAKE THE COEFFICIENT OF x or y the same and then add or subtract the equations. One of them gets eliminated. Find out the value of the other. Substitute its value in any equation and find the value of the other.


1st

5x-2y=6
3x+2y=26

Here coeff of y is the same. JUST ADD the 2 equations
8x = 32
x = 4
5*4 -2y = 6
20 - 2y = 6
-2y = -14
y = 7
answer x = 4 y = 7

2nd

3x+2y=11
x+2y=1

JUST SUBTRACT

2x = 10
x = 5
5 + 2y = 1
2y = -4
y = -2
ANSWER x = 5 y = -2

3rd

2x+3y=12
x+4y=11

MULTIPLY EQUATION 2 by 2 BOTH SIDES

2x + 8y = 22

SUBTRACT EQUATION 1 from it
5y = 10
y = 2
x = 3 ANSWER

By elimination.

Study it, it's simple stuff.