x+2y=9
2x+4y=7

3x+2y=14; x+4y=7

Classify the following pairs of lines as coincident, parallel, perpendicular or intersecting : (i) 6x+14y-16=0 , 12x+28y-32=0 (ii) 3x-4y=8 , 3x+4y=11 (iii) 5x-2y=7 , 2y-5x=-7 (iv) 4x+7y=19 , 7x-4y=-2 (v) x-2y=7 , 4y-2x=13

If 3x+2y=12 and x y=6 , find the value of 9x^2+4y^2

If 3x+2y=12 and x y=6, find the value of 9x^2+4y^2

3x-y=7; 2x+4y=0

Solve : 3x+ 2y = 14 - x+ 4y = 7

Add: 3x + 5y -4,-9x + 4y and 2x-5y+7.

Show that each of the following systems of linear equations is consistent and also find their solutions: 6x+4y=2 9x+6y=3 2x+3y=5 6x+9y=15 5x+3y+7z=4 3x+26 y+2z=9 7x+2y+10 z=5 x-y+z=3 2x+y-z=2 -x-2y+2z=1 x+y+z=6 x+2y+3z=14 x+4y+7z=30 2x+2y-2z=1 4x+4y-z=2 6x+6y+2z=3

The line 3x + 2y + 7 = 0 and 6x + 4y + 9 = 0 are "___________" to each other .