Question

1°) Resolva os sistemas de equações abaixo utilizando qualquer método sabendo que U=IR ×IR.​

Answer 1

a)

2x+3y=2

x-y=8 ×(3)

2x+3y=2

+3x-3y=24

5x=26

x=26/5

x-y=8

y=x-8

y=26/5 -8

y=(26-40)/5

y=-14/5

S={26/5, -14/5}

b)

x+2y=3

9x-y=2 (2)

x+2y=3

+18x-2y=4

19x=7

x=7/19

9x-y=2

y=9x-2

y=9.7/19 -2

y=63/19-2

y=(63-38)/19

y=25/19

S={ 7/19, 25/19}

c) -2x-y=1

+y=-x-5

-2x=-x-5+1

-2x+x=-4

-x=-4(-1)

x=4

y=-x-5

y=-4-5

y=-9

S={4,-9}