Question

bună ziua! ex 48 punctele c si d​

Answer 1

Răspuns:

Explicație pas cu pas:

0,5x = 0,2y

5x = 2y

x = 2y/5

c)

5x - y = 5*2y/5 - y = 2y - y = y

2x + y = 2*2y/5 + y = 4y/5 + 5y/5 = 9y/5

y/(9y/5) = 5/9

d)

9x + 2y = 9*2y/5 + 2y = 18y/5 + 10y/5 = 28y/5

2x = 2*2y/5 = 4y/5

(28y/5)/(4y/5) = 7