Question

2x+y=7 and 7x-4y= 2 what is value of x+y detail explanation

Answer 1

Given :

2x + y = 7 ...(i)
7x - 4y = 2 ...(ii)

From (i), we get

y = 7 - 2x ...(iii)

From (ii), we get

7x - 4 (7 - 2x) = 2
or, 7x - 28 + 8x = 2
or, 15x = 30
or, x = 2

Putting x = 2 in (iii), we get

y = 7 - 2 (2) = 7 - 4 = 3

So,
x + y
= 2 + 3
= 5

Answer 2

2x+y=7....(i)

7x-4y=2...(ii)

Multiply (i) by 4.

We get :

8x+4y=28....(iii)

Solve (i) and (iii)

8x+4y=28

+7x-4y=2

_________
15x=30

x=2.

Substitute value of x in (ii)

7(2)-4y=2

14-4y=2

-4y=2-14

-4y=-12

y=3.

Now

x+y=2+3=5.

Hope it helps u!!!