The answer is 5 and associative property
Division using multiples of 10 is different than how most of us learned how to divide. <span>The idea of multiple is what number can 10 go into without a remainder. That is easy. Ten ends in a zero. Thus 10 goes into numbers ending in zero. An example is 60. Ten ends in a zero; 60 ends in a zero. It will divide evenly. </span>
Isolate the variable by dividing each side by factors that don't contain the variable.
x = 1
-6+3x+4=2-4x+3
-8+7x+1=0
7x=7
x=1
Find a common multiple in between the denominators.
10 and 3 and 5 -> the least common multiple is 30.
Change all the denominators to 30 by multiplying the top and bottom by the same number.
9/10=27/30
1/3=10/30
1/5=6/30
Subtract!
27/39-10/30-6/30=11/30
The answer is 11/30
Hope this helps!