Question

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

Answer 1

Answer:

m=-1

Step-by-step explanation:

2x+3y=11............. (eqn 1)

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

Subtract eqn 1 from eqn 2

7y=35

y=5

Substitute for y in eqn 1

2x+3(5)=11

2x+15=11

2x=11-15

2x=-4

x=-2

y=mx+3

5=-2m+3

5-3=-2m

2=-2m

m=-1

Answer 2

Answer:Here,

1. 2x+3y=11..........(i)
2. 2x-4y= -24......... (ii)

Subtracting (ii) from (i),we get

2x+3y=11

- 2x+4y=24

___________

7y =35

y=5

Substituting y = 5 in (i) we get

2x+3×5=11

or,2x +15 =11

or,2x = 11- 15

or,x= -2

Now,

We know,y=mx+c

5=m ×(-2) +3

or,2=m×(-2)

or,2/-2 =m

m= -1