Question

Daca 2a + 3b 13
______ = __
5a - 2b 4
Determinati valoarea raportului b-a
___
b+a

Answer 1

bafta in continuare:))

Answer 2

$\frac{2a + 3b}{5a - 2b} = \frac{13}{4}$;
$\frac{b-a}{b + a} = ?$

⇒ 4 * (2a + 3b) = 13 * (5a - 2b)
8a + 12b = 65a - 26b
a + 7a = 65a - 38b
0 = 57a - 38b
57a = 38b
a = $\frac{57}{38} * b$



$\frac{b - \frac{57}{38} * b}{b + \frac{57}{38} * b} =$

$= \frac{b(1 - \frac{57}{38} )}{b(1 + \frac{57}{38})}$

$= \frac{ 1 - \frac{57}{38} } { 1 + \frac{57}{38} }$

$= \frac{ 1 - 1,5 } { 1 + 1,5 }$

$= \frac{0,5} {2,5}$

= 0,2;