Question

hi guys please help me​

Answer 1

Step-by-step explanation:

$(i) {a}^{2} - 64$

$= ( {a)}^{2} - ( {8)}^{2}$

$= (a + 8)(a - 8)$

$(ii)20 {a}^{2} - 45 {b}^{2}$

$= 5(4 {a}^{2} - 9 {b}^{2} )$

$= 5( {2a)}^{2} - ( {3b)}^{2}$

$= 5(2a + 3b)(2a - 3b)$

$(iii)32 {x}^{2} {y}^{2} - 8$

$= 8(4 {x}^{2} {y}^{2} - 1)$

$= 8( {2xy)}^{2} - ( {1)}^{2}$

$= 8(2xy + 1)(2xy - 1)$

$(iv) {x}^{2} - 2xy + {y}^{2} - {z}^{2}$

$= ( {x - y)}^{2} - {z}^{2}$

$= (x - y + z)(x - y - z)$

$(v)49 {x}^{2} - 1$

$= ( {7x)}^{2} - ( {1)}^{2}$

$= (7x + 1)(7x - 1)$