Question

Rezolvati folosind factorul comun:
1. 9+9•15-9•13
2. 2017+42•2017-43•2017

Dau coroana celui mai bun raspuns!

Answer 1

9+9x15-9x13 = 9(1+15-13) = 9(16-13) = 9x3=27

2017+42 x 2017 -43 x 2017 = 2017 (1+42-43) = 2017 x 0 = 0

Answer 2

$9+9\cdot15-9\cdot13= \\ \\ 9\cdot(1+15-13) = \\ \\ 9\cdot 3 = \boxed{27} \\ \\ \\ \\ 2017+42 \cdot 2017 -43\cdot 2017 = \\ \\ 2017\cdot(1+42-43) = \\ \\ 2017 \cdot 0 = \boxed{0}$