solve by elimination method 2x+7y=5 , -3x+8y=-11
Answers
Solution :-
Elimination method is used to solve the linear equations in two variables where one variable is eliminated.
The given equation are
2x + 7y = 5. eqn( 1 )
-3x + 8y = 11. eqn ( 2 )
Multiply eq( 1 )by 3 and eq( 2 ) by 2
3( 2x + 7y = 5 )
6x + 21y = 15.
6x + 21y -15. eqn( 3 )
2( -3x + 8y = -11 )
-6x + 16y = -22.
-6x + 16y +22 = 0. eqn( 4 )
Add eqn( 3 ) and eqn( 4 )
6x + 21y - 15 + ( -6x + 16y + 22) = 0
6x + 21y - 15 -6x + 16y + 22 = 0
37y + 37 = 0
37y = -37
y = -37/37
y = -1
Subsitute the value of y in eqn ( 1)
2x + 7(-1 ) = 5
2x - 7 = 5
2x = 5 + 7
x = 12/2
x = 6
Hence, The value of x and y are
6 and ( -1) 
Answer:
Solution:
Elimination method is used to solve the linear equations in two variables where one variable is eliminated.
The given equation are
2x + 7y = 5. eqn( 1 )
-3x + 8y = 11. eqn ( 2 )
Multiply eq( 1 )by 3 and eq( 2 ) by 2
3( 2x + 7y = 5 )
6x + 21y = 15.
6x + 21y -15. eqn( 3 )
2( -3x + 8y = -11 )
-6x + 16y = -22.
-6x + 16y +22 = 0. eqn( 4 )
Add eqn( 3 ) and eqn( 4 )
6x + 21y - 15 + ( -6x + 16y + 22) = 0
6x + 21y - 15 -6x + 16y + 22 = 0
37y + 37 = 0
37y = -37
y = -37/37
y = -1
Subsitute the value of y in eqn ( 1)
2x + 7(-1 ) = 5
2x - 7 = 5
2x = 5 + 7
x = 12/2
x = 6