Question

Aflati numerele a si b stiind ca sunt direct proportionale cu 2 si 9 si produsul lor este 72.
#ajutati-marepedepls

Answer 1

{ a,b } d.p { 2,9 } 
-----------------/-------
a x b  = 72
---------------------//---

a / 2 = b /  9 = K 

a / 2 = K => a = 2K
b / 9 = K= > b = 9 K

2 K x  9 K = 72
18 K² = 72
K² = 72 : 18
K² =  4
K = 2 

a = 2 x 2 = 4

b = 2 x 9 =  18

Answer 2

a/2=b/9=k
a*b=72
----------------------------
a=2k
b=9k
2k*9k=72
18k²=72
k²=72:18
k²=4
k=√4
k=2

a=2k=2*2=4
b=9k=9*2=18

Verificare:4*18=72