80 degrees. 145 = (4x+5) + (6x-10) = 10x-5... so 10x = 150, x = 15. LMN = 6x-10 = 6(15) - 10 = 80.
        
             
        
        
        
replace the numbers given for x & y so 
the equation becomes 3*(-3) + 2*(-4) =
3*-3 = -9
2*-4 = -8
-9 + -8 = -17
 
        
             
        
        
        
Trapezoid
it has four sides and 1 set of parallel lines