Question

Where do the graphs of these equations intersect?
3x+y=4 ((0,4) ???
X+y=2 (0,2) ???

Write an equation that results from adding the 2 equations in the above problem.

Does this equation also pass through (1,1) ??

Answer 1

3x+y=4
X+y=2

subtract the two equations:
2x=3 ,or x=1. If x=1, then y=1 (second equation), so they intersect at (1,1).

Answer 2

3 x + y = 4
1 x + y = 2
----------------- subtract
2 x + 0 = 2
x = 1
1 + y = 2
y = 1 so the two lines intersect at (1 , 1)

now add the original two lines
4 x + 2 y = 6
if y = 1
4x + 2 = 6
4 x = 4
x = 1
so yes , the sum goes through (1,1)

Answer 3

Your first question probably was:
Where do the graphs of these equations intersect the x-axis ?

the answers you gave are correct