bonsoir
100n² - 49 = ( 10 n - 7 ) ( 10 n + 7 )
64 y² - 36 = ( 8 y - 6 ) ( 8 y + 6 )
81 n² - 9 = ( 9 n - 3 ) ( 9 n + 3 )
( 2 + a ) ² - 16 = ( 2 + a - 4 ) ( 2 + a + 4 ) = ( a - 2 ) ( a + 6 )
( x + 3 )² - x² = ( x + 3 - x ) ( x + 3 + x ) = 3 ( 2 x + 3 )
Bonsoir,
a) 100n² - 49
= a² -b² = (a-b) (a+b)
= (10n-7) (10n+7)
b) 64y² - 36
= (8y-6) (8y+6)
c) 81n²- 9
= (9n -3) (9n+3)
d) (2+a)² - 16
= (2+a-4) (2+a+4)
= (a-2) ( a-6)
e) (x+3)² -x²
= (x+3-x)= (x+3+x)
= (3) ( 2x+3)