Question

a² = 4a +16

prosze o rozwiazanie

Answer 1

a^2 = 4a + 16

a^2 - 4a - 16 = 0

a^2 - 2 * 2 * a + 2^2 - 20 = 0

(a - 2)^2 - 20 = 0

(a - 2)^2 = 20

(a - 2)^2 = (√20)²

a - 2 = √20     lub   a - 2 = -√20

a = 2√5 + 2              a = -2√5 + 2