4х-6х=10+8
-2х=18
х=18:(-2)
х=-9
6 13/24 - ((14 7/24 - 10 31/48) - (2 3/4 - 1 7/12)) - 1 1/16 = 157/24 - ((343/24 - 511/48) - (11/4 - 19/12)) - 17/16 = 157/24 - ((686-511)/48 - (33-19)/12) - 17/16 = 157/24 - (175/48 - 14/12) - 17/16 = 157/24 - (175-56)/48 - 17/16 = 157/24 - 119/48 - 17/16 = (314-119-51)/48 = 144/48 = 3
1) _2307 2) + 1854
453 636
1854 2490
ВС=6-АВ, т.к. АВ=CD, то <em>ВС=6-CD</em>
BD=ВС+CD=6-CD+CD=<u><em>6см</em></u>