Question

Solve the following equations for the unknown: (a + 2)(2a +5) = 2(a + 1)² + 13

Answer 1

(a + 2)(2a +5) = 2(a + 1)² + 13
Collecting like terms,
⇒ a(2a + 5) + 2 (2a + 5) = 2a² + 2 + 4a + 13
⇒ 2a² + 5a + 4a + 10 - (2a² + 4a + 15) = 0
⇒ 5a + 10 - 15 = 0
⇒ a = 1 is the unknown.