Question

if 2x+2y= 18 then x+y= 9solve this by linear equations and represent it on graph​

Answer 1

Given question:

2x + 2y = 18.........(1)

x + y = 9............(2)

We use elimination method,

2x + 2y = 18

x + y = 9

( - ) ( + ) (-)

x + 3y = 9........(3)

Solving equation (3) to get y value.

3y = 9

y = 9/3

y = 3

Substitute y value in equation (1)

2x + 2(3) = 18

2x + 6 = 18

2x = 18 - 6

2x = 12

x = 12/2

x = 6

It's confusing but don't worry I will verify it.

Using equation (1) and substitute x value and y value.

2(6) + 2(3) = 18

12 + 6 = 18

18 = 18

Using equation (2) and substitute x value and y value.

6 + 3 = 9

9 = 9

Hence, verified it.