УПРОСТИТЕ уравнения: а) 15a*4= б) 3b*12= в) 17a*5b= г) 11a*7b= д) c*18*d*3= е) x*9*4*y=

[latex]15a*4=60a[/latex] ======= [latex]3b*12=36b[/latex] ======== [latex]17a*5b=85ab[/latex] ------ [latex]11a*7b=77ab[/latex] ======= [latex]c*18*d*3=54cd[/latex] ======= [latex]x*9*4*y=36xy[/latex]