Question

write four solutions for 2x+y=7

Answer 1

2x+y=7for x=0, 
2×0 + y = 7
⇒ 0 + y = 7
⇒ y = 7
So (0,7) is a solution.

for x=1, 
2×1 + y = 7
⇒ 2 + y = 7
⇒ y = 7-2 = 5
So (1,5) is a solution.

for x=2, 
2×2 + y = 7
⇒ 4 + y = 7
⇒ y = 7-4 = 3
So (2,3) is a solution.

for x=3, 
2×3 + y = 7
⇒ 6 + y = 7
⇒ y = 7-6 = 1
So (3,1) is a solution.

Four solutions are :(0,7), (1,5), (2,3) and (3,1).

Answer 2

2x+y=7
y = 7-2x
putting different values of x,will get corresponding value of y.
1. x =0
y = 7-2(0) 
y =5
2. x = 1
y = 7-2(1)
y = 5
3. x = 2
y = 7-2(2)
y =3
4. x=4
y = 7- 2(4)
y = -1
so the four solutions are  (0,7) , (1,5) , (2,3) , (4, -1)