The mid segment is half of the base
so
1/2(6x-12) = 2x + 10
3x - 6 = 2x + 10 I distributed the 1/2
-2x -2x subtract 2x from both sides
x -6 = + 10
+6 +6 Add 6 from both sides
x = 16
now we know x is 16 and BE is 2x+10
so I can find it by plugging 16 in
2(16) + 10
32 + 10 = 42 is BE