Hello :
the slope is : (YD - YC)/(XD -XC)
(0+5)/(6-3) = 5/3
the slope is 5/3
an equation is y=(5/3)x+b
Line CD passes through points D(6, 0): 0 = (5/3)(6)+b
b = -10
y=(5/3)x-10
-(5/3)x+y = -10
-5x+3y = -30
conclusion :
the equation of line CD in standard form is 5x-3y = 30
