Question

Diket sistem persamaan 2x - 3y = 18 dan x + 4y = -2. nilai x + y adl..
dijawab ya kak bsok dikumpulkan jgn lupa kasih cara♥

Answer 1

X+4y = -2
x= -2 -4y
substitusikan x ke
2(-2 -4y) -3y = 18
-4 -8y -3y =18
-4 -11y= 18
-11y = 18 +4
-11y = 22
y= 22/-11
y= -2

x +4y = -2
x +4(-2) = -2
x -8 =-2
x= -2 +8
x= 6

x+y= 6 -2= 4

Answer 2

2x-3y=18 dikali 1 => 2x-3y=18
x+4y=-2 dikali 2 => 2x+8y=-4 -
                                  -11y=22
                                       y=-2
sub. y=-2 ke pers. 
x+4y = -2
x+4(-2)=-2
x-8=-2
x=6

x+y=6+(-2)= 4