Question

ma puteti ajuta urgent?dau coroana​

Answer 1

Explicație pas cu pas:

a=2/3

S =a+b

S=2/3+b

D=2/3-b

S/D=5

(2/3+b)/(2/3-b)=5

(2/3+3b/3)/(2/3-3b/3)=5

[(2+3b)/3] /[(2-3b)/3]=5

(2+3b)/3×3/(2-3b)=5

(2+3b) /(2-3b) =5

2+3b=5(2-3b)

2+3b=10-15b

3b+15b=10-2

18b=8

b=8/18

b=4/9