Respuesta :

fieryanswererft

Answer:

( 7 , 4 )

given:

  • 4x + 10y = 68
  • 4x - y = 24

make y the subject in equation 2:

4x - y = 24

-y = 24 - 4x

y = 4x - 24

insert this in equation 1:

4x + 10y = 68

4x + 10(4x - 24) = 68

4x + 40x - 240 = 68

44x = 68 + 240

44x = 308

x = 7

solve for y:

y = 4x - 24

y = 4(7) - 24

y = 4

boatengalbert291
4x + 10y =68 ......(1)
4x - y = 24 .......(2)
From equation (2)
y = 4x - 24 .....(3)
Put Eqn (3) into Eqn (1)
4x + 10(4x - 24)=68
4x + 40x -240 = 68
44x - 240 = 68
44x = 68 + 240
44x = 308
Divide through by 44
x = 7
Put x = 7 in Eqn(3)
y = 4(7) -24
y = 28 -24
y = 4

(x,y) = (7 , 4)

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