Question

find the value of Dy
3x+y=1. and 2x-11y=3​

Answer 1

Answer:

x= 2/5

y= -1/5

Step-by-step explanation:

$2\times (3x + y = 1) = 6x + 2y = 2 \\ 3 \times (2x - 11y = 3) = 6x - 33y = 9$

eliminate x by subtracting one eqn from the other and find y then put y in any of the eqn and find x

Answer 2

3x+y=1--------(1)

2x-11y=3-------(2)

Lets compare eq(1) with (3) and (2) with (4)

a1x+b1y=c1--------(3)

a2x-b2y=c2------(4)

a1=3, b1=1, c1=1

a2=2, b2=-11, c2=3

Dy=

|a1 c1| |3 1|

|a2 c2|=|2 3|=(1×2)-(3×3)=2-9=-7