Question

Algebra.. solve x+y=3; 3x-2y-4=4=0 by determinant method find D​

Answer 1

Answer:

x-y=3 . . . [.]

3x-2y-4=4 . . . [..]

In equation [..]

3x-2y-4=4

3x-2y=4+4

3x-2y=8

In equation [.] and [..]

x-y=3 x 2 . . . [...]

3x-2y=8 x 1 . . . [....]

By elimination method

subtracting [...] from [....]

2x-2y=6

3x-2y=8

[-]  [+] [-]

x        =-2

substittuting value in equation [.]

x-y=3  

-2-y=3

-y=3+2

y=-5

proof answer is correct:

x=-2

y=-5

substitute in equation

x-y=3

substituting values

-2-(-5)=3

-2+5=3

3=3

hence solved.