Question

53. Resolver os seguintes sistemas no universo U=R?
a) 4x – 3y = 0
4x + 2y = 3

b) - 2x + 5y = 1
2x – 3y = 5

c) 2a - 7b =2
a - 3b = -3

Me ajudem !!!

Answer 1

a) 4x – 3y = 0

4x + 2y = 3

4x-3y=0

4x=3y

4x+2y=3

(3y)+2y=3

5y=3

y=3/5

4x=3y

4x=3(3/5)

4x=9/5

x=(9/5)/4

x=9/20

s= {( 9/20 , 3/5 )}

b) - 2x + 5y = 1

2x – 3y = 5

-2x+5y=1

-2x=1-5y (-1)

2x=5y-1

2x-3y = 5

(5y-1) -3y =5

5y-3y = 5+1

2y = 6

y= 6/2

y= 3

2x=5y-1

2x=5(3) -1

2x= 15-1

2x=14

x=14/2

x=7

s= {( 7 , 3 )}

c) 2a - 7b =2

a - 3b = -3

a - 3b = -3

a = -3 +3b

2a -7b = 2

2(-3+3b)-7b =2

-6 +6b -7b =2

-b = 2+6

-b = 8

b= -8

a= -3+3b

a= -3 +3(-8)

a= -3 -24

a= -27

s= {( -27 , -8 )}