Question

Dau coroana si 28 de puncte.
Materie clasa a 10 a.
Multumesc anticipat​

Answer 1

$u \: colinar \: cu \: v \: = > \frac{a}{4} = \frac{3}{a + 4} = \\ a(a + 4) = 12 = \\ {a}^{2} + 4a = 12 \\ {a}^{2} + 4a - 12 = 0 \\ Δ = 16 + 48 = 64 \\ a1 = \frac{ - 4 + 16}{2} = 6 \\ a2 = \frac{ - 4 - 16}{2} = - 10$