How would start to solve: log-4x-log4=1

log -4x-log4=1

when subtracting logs of the same base, you divide)

log (-4x/4)=1

log (-x) = 1

inverse of log is take it to the power of 10

-x = 10^1

-x = 10

divide by -1

x =-10

Associative property and commutative property true for addition, not true for subtraction.

Step-by-step explanation:

Associative property and commutative property true for addition.

i) a + (b + c) = (a + b) + c  ---> Associative property of addition

ii) a + b = b + a --> commutative property of addition.

These properties not true for subtraction.

That's the reason Juan used additive inverse before applying these property.

Hope this will helpful.

Thank you.