Question

3. Given this quadratic equation, 2x2 - x - 28 = 0,

Answer 1

Answer:

a) (2x+7)(x-4)

b) x = -7/2 and x = 4

Step-by-step explanation:

a) (2x  ?)(x  ?)

set up the above and considered factors of 28 that, when paired with 2, would give me -1x and -28  → (1·28, 2·14, 4·7)

after trial-and-error, found that 4 and 7 worked (used un-FOIL)

b) 2x + 7 = 0

2x = -7

x = -7/2

*********

x-4 = 0

x = 4