In △ABC, ∠B = 90°, AD and CE are the medians drawn from A and C, respectively. If AC = 10 cm and AD = \(\sqrt{55}\,\text{cm}\) then the length of CE is:
\(2\sqrt{15}\,\text{cm}\)
\(\sqrt{70}\,\text{cm}\)
\(\sqrt{66}\,\text{cm}\)
If a2 + 4b2 + 25c2 + 18 = 2(a - 2b + 20c), then what is the value of (a + 2b + 5c) ?