Question

Factorise 4b^2 + 16b

Answer 1

Factorise 4b² + 16b  ⇒ 4b(b+4)

expand (a-1)(a-2) ⇒ a(a-2) - 1(a-2) ⇒ a² - 2a - 1a + 2 ⇒a² - 3a + 2

factorise x² + 8x + 7 ⇒(x + 1) (x + 7)

evaluate y⁶ / y² ⇒ y * y * y * y * y * y / y * y = y⁴

if x = -1 and y = 5, find z when z = x² + 2y² ;
z = -1² + 2(5²) ⇒ 1 + 2(25) ⇒1 + 50 = 51

Make x the subject: y = 4x - 3
     y = 4x - 3
+3            +3
3 + y = 4x
÷4        ÷4    
(3+y)/4 = x