Question

calculati 5a-3b(b+c)+145:5-8 daca 3a-2b=b-2a+3c
va rog ajutati-ma!

Answer 1

Corectez:  5 a - 3 x ( b + c ) in loc de 3 b ( b + c ) !

3 a - 2 b = b - 2 a + 3 c

3 a + 2 a = 2 b + b + 3 c

5 a = 3 b + 3 c

5 a = 3 ( b + c )

__________________

5 a - 3 x ( b + c ) + 145 : 5 - 8 = 21

= 3 x ( b + c ) - 3 x ( b + c ) + 29 - 8 =

=  0 + 21 =

= 21