Question

49ab square - 81 c square a
​

Answer 1

Answer:

You may notice that

49

=

7

2

and

81

=

9

2

are both squares.

Explanation:

So

49

a

2

=

(

7

a

)

2

and

81

b

2

=

(

9

b

)

2

are also squares, and then we can use the special product of the form:

x

2

−

y

2

=

(

x

+

y

)

(

x

−

y

)

=

(

7

a

+

9

b

)

(

7

a

−

9

b

)