deleted.

sinclairdragon428 Jun 10, 2019

edited by
sinclairdragon428
Jun 10, 2019

edited by sinclairdragon428 Jun 10, 2019

edited by sinclairdragon428 Nov 20, 2019

edited by sinclairdragon428 Jun 10, 2019

edited by sinclairdragon428 Nov 20, 2019

#2**+1 **

x * y = 56..............................(1)

7*1/x + 14*1/y = 4...................(2)

Can you solve the 2 simultaneous equations? Try it.

Guest Jun 10, 2019

edited by
Guest
Jun 10, 2019

#3**+1 **

xy = 56 ⇒ y = 56/x

And

7 (1/x) + 14(1/y) = 4

7/x + 14/y = 4

7/x + 14 / (56/x) = 4

7/x + (14/56)x = 4

7/x + (1/4) x = 4 multiply through by 4x

28 + x^2 = 16x rearrange as

x^2 - 16x + 28 = 0 factor as

(x - 14) ( x - 2) = 0

Set each factor to 0 and solve for x and we have that

x = 14 or x = 2

And y =

56/14 = 4 or 56/2 = 28

So (x,y) = (2, 28)

CPhill Jun 10, 2019