Question

Solve
3x+y+1=0
2x-3y+8=0
by Cross multiplication
method​

Answer 1

Answer:

3x+y+1=0....eq(1)

2x-3y+8=0.....eq(2)

ax+by+c=3x+y+1

a1=3;b1=1;c1=1

ax+by+c=2x-3y+1

a2=2;b2=(-3);c2=1

b1 c1 a1 b1

b2 c2 a2 b2

[x/(b1×c2)-(b2×c1)]=[y/(c1×a2)-(c2×a1)]=

[1/(a1×a2)-(a2×b1)]

1 1 3 1

-3 8 2 -3

[x/(1×8)-(-3×1)]=[y/(1×2)-(8×3)]=

[1/(3×-3)-(2×1)]

$\frac{x}{(8) - ( - 3)} = \frac{y}{(2) - (24)} = \frac{1}{( - 9) - (2)} \\ \frac{x}{11} = \frac{y}{( - 22)} = \frac{1}{ (- 11)} \\ \frac{x}{11} = \frac{1}{ (- 11)} \\ - 11x = 11 \\ x = \frac{11}{(- 11)} \\ x = ( - 1) \\ \frac{y}{ (-22)} = \frac{1}{( - 11)} \\ - 11y = - 22 \\ y = \frac{ (-22)}{ (-11)} \\ y = \frac{( - 2)}{ ( - 1)} \\ y = 2$

Therefore,x=(-1) and y=2

HOPE IT HELPS YOU.........