Question

factoring difference of two squares
1.a2-81
2.c2-16
3.25e2-16
4.4*2-49
5.81x2-400y

Answer 1

FROM QUESTION 1 TO 4 IN ONE IDENTITY = (a)² – (b)² = ( a + b ) ( a – b )

1) a² – 81

= (a)² – (9)²

= ( a + 9 ) ( a – 9 )

2) c² – 16

= (c)² – (4)²

= ( c + 4 ) ( c – 4 )

3) 25e² – 16

= (5e)² – (4)²

= ( 5e + 4 ) ( 5e – 4 )

4) 4² – 49

= (4)² – (7)²

= ( 4 + 7 ) ( 4 – 7 )

5 ) 81x² – 400y⁴

= (9x)² – (20y²)

= ( 9x + 20y² ) ( 9x – 20y² )