Question

solve the following pairs of linear equation by substitution method x+y=7,2x-3y=-11




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Answer 1

Answer:

x+y=7 (eq-1)

2x-3y=-11(eq 2)

from equation 1

x=7-y

put x=7-y in equation 2

2(7-y) -3y= -11

14-2y-3y= -11

-5y= -11-14

-5y = -25

y = -25/-5

=5

put y= 5 in equation 1

x+5=7

x=7-5

=2

Step-by-step explanation:

hope it's help you

Answer 2

Answer :

x = 2 , y = 5

Solution :

Here ,

The given equations are ;

x + y = 7 ------(1)

2x - 3y = -11 ----------(2)

Using eq-(1) , we have ;

=> x + y = 7

=> x = 7 - y --------(3)

Now ,

Substituting x = 7 - y in eq-(2) , we get ;

=> 2x - 3y = -11

=> 2(7 - y) - 3y = -11

=> 14 - 2y - 3y = -11

=> -2y - 3y = -11 - 14

=> -5y = -25

=> y = -25/-5

=> y = 5

Now ,

Putting y = 5 in eq-(3) , we get ;

=> x = 7 - y

=> x = 7 - 5

=> x = 2

Hence ,

x = 2 , y = 5