Question

by elimination method

Answer 1

x/10 + y/5 - 1 = 0

=> (x+2y-10) / 10 = 0

=> x + 2y - 10 = 0

On multiplying both sides by 2,we get

2x + 4y - 20 = 0 ---------(1)

Now,

x/8 + y/6 = 15

=> x/8 + y/6 - 15 = 0

=> (3x + 4y -360) /24 = 0

=> 3x + 4y - 360 = 0 --------(2)

Now,

On subtracting equation 1 from 2, we get

3x +4y - 360 - (2x +4y - 20) = 0

=> 3x +4y - 360 - 2x - 4y + 20 = 0

=> x - 340 = 0

=> x = 340

Now, on putting the value of x in equation (1),we get

2(340) +4y - 20 = 0

=> 680 + 4y - 20 = 0

=> 4y + 660 = 0

=> 4y = - 660

=> y = - 165

Answer 2

x/10 + y/5 = 1   ----- (1)

x/8 + y/6 = 15  ------ (2)

On solving (1) * 5 & (2) * 6, we get

5x/10 + 5y/5 = 5

6x/8 + 6y/6 = 90

(-)          (-)       (-)
-----------------------

x/2 - 3x/4 = -85

2x - 3x = -340

-x = -340

x = 340.


Substitute x = -340 in (2), we get

x/8 + y/6 = 15

340/8 + y/6 = 15

6(340) + 8y = 15 * 48

2040 + 8y = 720

8y = 720 - 2040

8y = -1320

y = -165.


Hope this helps!