This is your answer. If you still need it:
3m/m-6 * 5m^3-30m^2/5m^2
First you need to put the numerators and the denominators together in the same "line" or "fraction if you would say.
(3m)(5m^3-30m^2)/(m-6)(5m^2)
Then you would use the distributive property and then multiply the expressions. No dividing yet.
15m^4-90m^3/5m^3-30m^2
Now you simplify with the power of exponents rule
15m-90m/5-30
Now you normally simplify by just subtracting
-75m/-25
Then simply simplify the constants
3m (The answer is 3m because -75/-25=3 positive whole numbers always stay on top [numerator], if it were negative and still on the denominator, using power of exponent rules, you would switch it up to the numerator, or "flipping" the constant or variable)