I. ` 8x+7y = 135" "` II.` 5x+6y = 99`
III.` 9y+8z= 121`

I. 7x + 6y = 110 II. 4x + 3y = 59 III. X + z = 15

5x - 4y + 8 = 0 7x + 6y - 9= 0

If 4x + 6y = 3 xy and 8x + 9y = 5xy then

If 5x + 6y : 8x + 5y = 8 : 9 , find : x : y .

Find the angle between the planes : (i) 3 x - 6y - 2z = 7 " " 2x + y - 2z = 5 (ii) 4 x + 8y + z = 8 " " and y + z = 4 (iii) 2 x - y + z =6 " " and x + y + 2z = 7 .

Solve the system: x + y - 2z = 0, 2x - 3y + z = 0, 3x - 7y + 10z = 0, 6x - 9y + 10z = 0.