Question

1. 3a-17-3*3+(3*2-1+5)=13
2. 23-a:3+(4*6-7*3)-4:4=19
Vă rog ajutați-mă repede !
* = cu ori

Answer 1

1)

$\bf 3a-17-3\cdot3\cdot(3\cdot2-1+5)=13$

$\bf 3a-17-9\cdot(6-1+5)=13$

$\bf 3a-17-9\cdot 10=13$

$\bf 3a-17-90=13$

$\bf 3a-107=13$

$\bf 3a=13+107$

$\bf 3a=120\:\:|:3$

$\boxed{\bf a = 40}$

2)

$\bf 23-a:3+(4\cdot6-7\cdot 3)-4:4=19$

$\bf 23-a:3+(24-21)-1=19$

$\bf 23-a:3+3-1=19$

$\bf 25-a:3=19$

$\bf 25-19 = a:3$

$\bf 6 = a:3\:\:\:\:|\cdot 3$

$\boxed{\bf a = 18}$