[1 Mark Question Answer]

Question 11 Mark

Expand : $( 5x - 3y - 2 )^2$

Answer

$( 5x - 3y - 2 )^2$
$= (5x)^2 + (3y)^2 + (2)^2 - 2(5x)(3y) + 2(3y)(2) - 2(2)(5x)$
$= 25x^2 + 9y^2 + 4 - 30xy + 12y - 20x$

Question 21 Mark

Expand : $( 5a - 3b + c )^2$

Answer

$( 5a - 3b + c)^2$
$= (5a)^2 + (3b)^2 + (c)^2 - 2(5a)(3b) - 2(3b)(c) + 2(c)(5a)$
$= 25a^2 + 9b^2 + c^2 - 30ab - 6bc + 10ca$

Question 31 Mark

Expand : $( x - 2y + 2 )^2$

Answer

$( x - 2y + 2 )^2$
$= x^2 + (2y)^2 + (2)^2 - 2(x)(2y) - 2(2y)(2) + 2(2)(x)$
$= x^2 + 4y^2 + 4 - 4xy - 8y + 4x$

Question 41 Mark

Expand : $( x + y - z )^2$

Answer

$( x + y - z )^2 $
$= x^2 + y^2 + z^2 + 2(x)(y) - 2(y)(z) - 2(z)(x)$
$= x^2 + y^2 + z^2 + 2xy - 2yz - 2zx$

Question 51 Mark

Expand : $( X - 8 ) ( X + 10 )$

Answer

$( X - 8 ) ( X + 10 ) $
$= X^2 - ( 8 - 10 )X - 8 x 10$
$= X^2 + 2X - 80$

Question 61 Mark

Expand : $( x + 8 )( x - 10 )$

Answer

$( x + 8 )( x - 10 )$
$= x^2 + ( 8 - 10 )x + 8 x (-10)$
$= x^2 - 2x - 80$

Question 71 Mark

Expand : $( x + 8 ) ( x + 10 )$

Answer

$( x + 8 )( x + 10 )$
$= x^2 + ( 8 + 10 )x + 8 x 10$
$= x^2 + 18x + 80$

MATHEMATICS [1 Mark Question Answer]