Question

Determine o valor de x e y para que os pares ordenado sejam iguais.

b) (6x, 12y) = (180,120)
c) (2x + 1, 5y - 3) = (19, 22)
d) (3x + 2y, 5x - 2y) = (21, 43)
e) (-9X + 6X, 5X + 6Y) = (-63, 43)
f) (x + y, 2x - y) = (7,11)

Precisa de CALCULOS..

Answer 1

b) (6x, 12y) = (180,120)
 6x = 180        12y = 120
  x = 30              y = 10
=====================================
c) (2x + 1, 5y - 3) = (19, 22)
    2x + 1 = 19       5y - 3 = 22
    2x = 19 - 1        5y = 22+3
    2x = 18              5y = 25
      x = 9                  y = 5
==========================================
d) (3x + 2y, 5x - 2y) = (21, 43)

3x + 2y = 21
5x - 2y =  43
    8x = 64 ==> x = 8

3x + 2y = 21 ==> 3y = 21 - 3x ==> 2y= 21-3.8
3y=21-24==> 3y= -3 ==> y = - 1

V = {( 8, - 1 ) } 
================================================

e) (-9X + 6X, 5X + 6Y) = (-63, 43) 

-9x +6x = - 63      
  -3x = -63(-1) ==> 3x = 63 ==> x = 21


5X + 6Y =  43 ==> 6y= 43-5x ==> 6y= 43-5.21
6y = 43-105
6y = - 62 ==> y = - 62/6
==============================================
f) (x + y, 2x - y) = (7,11)
 
   x + y = 7
   x - y = 11
      2x = 18
      x = 9

x + y = 7 ==> y = 7 - x ==> y = 7 - 9 ==> y = - 2

V = {(9, - 2 )}