Factorise the following :
$x^{2} + 2 x y - 99 y^{2}$

Open in App

Solution

$x^{2} + 2 x y - 99 y^{2}$
= $x^{2} + 11 x y - 9 x y - 99 y^{2}$ ..... [Now,as $- 99 = - 11 \times 9 a n d - 2 = - 11 + 9]$
= $x (x + 11 y) - 9 y (x + 11 y)$
= $(x + 11 y) (x - 9 y)$

Suggest Corrections

Similar questions

Factorise :

$(i) 2 a^{3} - 50 a (i i) 54 a^{2} b^{2} - 6 (i i i) 64 a^{2} b - 144 b^{3} (i v) (2 x - y)^{3} - (2 x - y) (v) x^{2} - 2 x y + y^{2} - z^{2} (v i) x^{2} - y^{2} - 2 y z - z^{2} (v i i) 7 a^{5} - 567 a (v i i i) 5 x^{2} - \frac{20 x^{4}}{9}$

Q. Factorise :

z^{2} - (x^{2} - 2 x y + y^{2})

Q. Factorise :

(x^{2} - 2 x y + y^{2}) - z^{2}

Q. Factorise the expression

x^{2} + 2 x y + y^{2} - 4 z^{2}

Q. Factorise :

16 - x^{2} - 2 x y - y^{2}

The factors are

Join BYJU'S Learning Program

Factorise the following :x2+2xy−99y2

x2+2xy−99y2=x2+11xy−9xy−99y2..... [Now,as −99=−11×9and−2=−11+9]=x(x+11y)−9y(x+11y)=(x+11y)(x−9y)

Factorise the following :
$x^{2} + 2 x y - 99 y^{2}$

$x^{2} + 2 x y - 99 y^{2}$
= $x^{2} + 11 x y - 9 x y - 99 y^{2}$ ..... [Now,as $- 99 = - 11 \times 9 a n d - 2 = - 11 + 9]$
= $x (x + 11 y) - 9 y (x + 11 y)$
= $(x + 11 y) (x - 9 y)$