Question

5/7*(2,8c-21/5d)-2,4*(5/6c-1,5d)

Answer 1

5/7(2,8с-4 1/5d)-2.4(5/6c-1.5d)=0,6д

1)  5/7(2,8с-4 1/5d)=5/7*2 8/10с-5/7*21/5д=5/7*28/10с-3д=2с-3д 

2)  2.4(5/6c-1.5d)=2 4/10*5/6с-3,6д=24/10*5/6с-3,6д=2с-3,6д 

3)2с-3д-2с+3,6д= 0,6д

Answer 2

=2с-3d-2c+3,6d=0,6d
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