Question

repede,dau 50 de puncte!!!​

Answer 1

Răspuns:

Explicație pas cu pas:

a)

x/y = 3/4

x/3 = y/4 = k

x = 3k

y = 4k

2x + 3y = 2*3k + 3*4k = 6k + 12k = 18k

4x + y = 4*3k + 4k = 12k + 4k = 16k

18k/16k = 18/16 = 9/8

b)

x/y = 7/9

x/7 = y/9 = k

x = 7k

y = 9k

x + 2y = 7k + 18k = 25k

3x + y = 21k + 9k = 30k

25k/30k = 5/6

c)

x/2 = y/5 = k

x = 2k

y = 5k

7x - 2y = 14k - 10k = 4k

x + 4y = 2k + 20k = 22k

4k/22k = 2/11

d)

x/3 = y/11 = k

x = 3k

y = 11k

10x - y = 30k - 11k = 19k

x + y = 3k + 11k = 14k

19k/14k = 19/14