5(-1,4a+3)-(1-2,5a)-4(0,8a+3), при a=5/7

Question

5(-1,4a+3)-(1-2,5a)-4(0,8a+3), при a=5/7

Answer 1

5(-1,4a+3)-(1-2,5a)-4(0,8a+3)=-7а+15-1+2,5а-3,2а-12=-7,7а-2= -7,7* 5/7 -2=-2.2-2=-4,2