Question

Resolva os sitemas da forma que achar mis convinienate (a) x+y=4 3x+y=28 (b) 4x+y=0 x+5y=-19 (c)-2x-3y=-9 x+4y=12 (d)-6x+2y=8 9x-y=8 me ajudem porfavor preciso pra hoje

Answer 1

(a) x+y=4 .(-1) => -x-y=-4

3x+y=28

corta o y e resolve o x:

2x = 28 - 4

2x = 24

x = 24/2

x = 12

x + y = 4

12 + y = 4

y= 4 -12

y = - 8

(b) 4x+y=0 .(-5) => -20x - 5y= 0

x+5y=-19

corta o y e resolve o x:

-19x = -19

x = -19/-19

x = 1

4x+y=0

4.1+y=0

4+y=0

y = -4

(c)-2x-3y=-9

x+4y=12 .(2) => 2x + 8y = 24

corta o x e resolve o y:

5y = 15

y = 15/5

y = 3

x+4y=12

x+4.3=12

x = 12 - 12

x = 0