Question 183583
5x+2y=16
2y=-5x+16
y=-5x/2+16/2
y=-5x/2+8 (red line)
3x+4y=7
4y=-3x+7
y=-3x/4+7/4 (green line)
{{{ graph( 300, 200, -6, 5, -10, 10, -5x/2 +8, -3x/4 +7/4) }}} (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions -5x/2 +8 and -3x/4 +7/4). 
Intercept: (25/7,-13/14)
5x+2y=16 multiply by -2 & add these 2 equations.
3x+4y=7
-10x-4y-32
--------------------
-7x-25
x=-25/-7
x=25/7 or 3.57 ans.
3*25/7+4y=7
75/7+4y=7
4y=7-75/7
4y=(7*7-75)/7
4y=(49-75)/7
4y=-26/7 ans.
y=-26/7*1/4
y=-26/28
y=-13/14