Question

i) x2 – 2x – 9. factorise it ​

Answer 1

Answer:

X^2 - 2x - 9 = (X^2 - 2x+1) - 10 =(X-1)^2 - (√10)^2 =(X - 1- √10)(x-1+ √10) X=1+√10 or x=1-√10.Step-by-step explanation:

Answer 2

$\huge{\underline{\bf{Given:}}}$

☞ x²-2x-9

$\huge{\underline{\underline{\sf{Solution:}}}}$

x²-2x-9 is in the form of ax²+bx+c = 0

Where ➝ a = 1, b = -2 & c = -9

$\boxed{\sf{x = \frac{-b±\sqrt{b²-4ac}}{2a}}}$

$→\;\Large{\sf{\frac{-(-2)±\sqrt{(-2)²-4(1)(-9)}}{2(1)}}}$

$→\;\Large{\sf{\frac{2±\sqrt{4+36}}{2}}}$

$→\;\Large{\sf{\frac{2±\sqrt{40}}{2}}}$

$→\:\Large{\sf{\frac{2+2\sqrt{10}}{2}}}$

AnSweR:

$➝\;{\bf{\red{x = 1+\sqrt{10}, 1-\sqrt{10}}}}$

Hope It Helps You ✌️