maths doubt

Asked by shamalmoghekar | 3rd Nov, 2020, 04:25: PM

Expert Answer:

1.
 
(a - b) = 7
 
Squaring on both the sides, we get
→ a2 - 2ab + b2 = 49
→ a2  + b2 = 49 +  2ab = 49 + 2(9) = 67....(ab = 9)
 
2.
(2x + 3)(3x - 1)
=2x(3x - 1) + 3(3x - 1)
= 6x2 - 2x + 9x - 3
= 6x2 + 7x - 3
 
Note: Please ask one question in one query.

Answered by Yasmeen Khan | 3rd Nov, 2020, 05:04: PM