You have the right idea that things need to get multiplied.
What should be done is that the entire fraction needs to get multipled by the lowest common denominator of both denominators.
Let's look at the complex numerator. Its denominators are 5 and x + 6. Nothing is common with these, so both pieces are needed.
The complex denominator has x - 3 as its denominator. With nothing in common between it and the complex numerator, that piece is needed.
So we multiply the entire complex fraction by (5)(x + 6)(x -3).
Numerator: 
= (x+6)(x-3) - (5)(5)(x-3)
= (x+6)(x-3) - 25(x-3)
= (x-3)(x + 6 - 25) <--- by group factoring the common x - 3
= (x -3)(x - 19)
Denominator:

Now we put the pieces together.
Our fraction simplies to (x - 3) (x - 19) / 125 (x + 6)
Answer:

Step-by-step explanation:
First find difference between the divisors and remainders.

Here, the difference between the divisors and remainders is equal.
So, the required number is equal to LCM of 

LCM of 
Required Number 
The answer to your question is 7a.
I think b sorry if it’s wrong :(
The value of m<span> must be greater than the value of</span><span> n</span><span>. When you multiply the binomials, the middle term is the result of combining the outside and inside products. So, </span>bx<span> = –</span>nx<span> + </span>mx<span>, or </span>bx<span> = (–</span>n<span> + </span>m)x<span>. This means that </span>b<span> = –</span>n<span> + </span>m<span>. When adding numbers with opposite signs, you subtract their absolute values, and keep the sign of the number having the larger absolute value. Since </span>b<span> is positive, </span>m<span>must have the larger absolute value.</span>