Question

@+@+@=18
#+#+#=9
&×&-&=6
#×@-#=??

Answer 1

@+@+@=18
3@=18
@=18/3
@=6

#+#+#=9
3#=9
#=9/3
#=3

&= 3
3x6-3 = 15

Answer 2

Olá Theus

3@ = 18
@ = 18/3 = 6

&*& - & = 6
x² - x - 6 = 0
d² = 1 + 24 = 25
d = 5

x1 = (1 + 5)/2 = 6/2 = 3
x2 = (1 - 5)/2 = -4/2 = -2

& = 3 ou -2

3# = 9
# = 9/3 = 3

#*@ - # = 3*6 - 3 = 18 - 3 = 15