Q3 of 137 Page 100

Factories:

81 – 49x2

We have,


81 – 49x2


= (9)2 – (7x)2


By using the formula a2 – b2 = (a + b)(a – b)


We get,


81 – 49x2 = (9)2 – (7x)2


= (9 + 7x)(9 – 7x)


More from this chapter

All 137 →
1

Factories:

x2 – 36

 2

Factories:

4a2 – 9

 4

Factories:

4x2 – 9y2

 5

Factories:

16a2 – 225b2