Question

Factorise q² - 10q + 21.

Answer 1

Answer:

${q}^{2} - 10q + 21$

${q}^{2} - 7q - 3q + 21$

$q(q - 7) - 3(q - 7)$

$(q - 7)(q - 3)$

Answer 2

Answer:

(q-3)(q-7)

Step-by-step explanation:

q^2 - 10q + 21 => Splitting the middle term method

=> -7 x -3 = 21.

(q^2 - 3q) - (7q + 21) (Sign will change as you multiply)

q(q - 3) - 7(q - 3)

Answer = (q - 7)(q -3)