Because EC is half of AD
BE = 1/2(DB)
Replace the letters with the equations:
p+2 = 0.5(3p-4)
Distribute the right side:
p+2 = 1.5p-2
Subtract p from each side:
2 = 0.5p -2
add 2 to each side:
4 = 0.5p
Divide both sides by 0.5 to get p
p = 4/0.5
p = 8
now replace p with 8 in the original equation:
BE = 8+2 = 10