Solve 2x+3y=11 and 2x–4y=–24 and hence find the value of ‘m’ for which y=mx+3

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 2. Solve 2x+3y=11 and 2x–4y=–24 and hence find the value of ‘m’ for which y=mx+3

Solution:

2x+3y=11---------(1)

2x-4y=-24--------(2)

By solving equation (1)

2x+3y=11

3y=11-2x

Y=(11-2x)/3--------(3)

Now substitute y=(11-2x)/3 in equation (2)

2x-4y=-24

2x-4(11-2x)/3=-24

(6x-44+8x)/3=24

(14x-44)/3=-24

14x-44=-72

14x=-72+44

14x=-28

X=-2

Substitute x=-2 in equation (3)

Y=(11-2x)/3

Y=11-2(2)/3=11+4/3=15/3=5

Y=5

Substitute x,y values in y=mx+3

Y=mx+3

5=m(-2)+3

5=-2m+3

-2m=5-3

-2m=2

m=-1


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