Question

factorise x2-21x+90by splitting the middle term​

Answer 1

Answer:

(x-6)(x-15)

Step-by-step explanation:

x2-21x+90

=x2-15x-6x+90

=x(x-15)-6(x-15)

=(x-6)(x-15)

PLS MARK BRAINLIEST

Answer 2

Answer:

$\boxed{\sf (x - 6)(x - 15)}$

Step-by-step explanation:

$\sf Factor \: the \: following: \\ \sf \implies {x}^{2} - 21x + 90 \\ \\ \sf The \: factors \: of \: 90 \: that \: sum \: to \: - 21 \\ \sf are \: - 6 \: and \: - 15. \\ \\ \sf So, \\ \sf \implies {x}^{2} + ( - 6 - 15)x + 90 \\ \\ \sf \implies {x}^{2} - 6x - 15x + 90 \\ \\ \sf \implies x(x - 6) - 15(x - 6) \\ \\ \sf \implies (x - 6)(x - 15)$