Question 842712
Use the FOIL Method, 
I'll do the first, you do the same for the second.
{{{(2m-9)(5m+4)=2m*5m+2m*4+5m*(-9)+(-9)(4)}}}
{{{(2m-9)(5m+4)=10m^2+8m-45m-36}}}
{{{(2m-9)(5m+4)=10m^2-37m-36}}}