Respuesta :

Answer:

24 and 32

Step-by-step explanation:

Let their present ages be x and y

Therefore, x

[tex] \frac{x}{y} = \frac{3}{4} [/tex]

we have 4x = 3y

4x - 3y = 0......................(I)

After four years,

[tex] \frac{x + 4}{y + 4} = \frac{7}{9} [/tex]

we have, 9(x + 4) = 7(y + 4)

9x + 36 = 7y + 28

9x - 7y = -8 ........................(ii)

Solving (I) and (ii) simultaneously

4x - 3y = 0

9x - 7y = -8

multiply eqn I by 9 and equation (ii) by 4 and subtract result

36x - 27y = 0...............(iii)

36x - 28y = -32...........(iv)

subtracting (iv) from (iii) we have,

y = 32

substituting y back in equation (I)

4x - 3y = 0

4x -3(32) = 0

4x - 96 = 0

4x = 96

x = 24

Their ages are 24 and 32