Please Help! In Triangle ABC, D is a point on side AB, E is a point on line AC and DE is a parallel to BC. Prove that AD:DE = AB:BC(first, prove AD:AB=DE:BC. Then interchange the means of the proportion

Can someone answer it, and plot it, for 20 points and brainliest answer? p.s. they're the same ! : )

Maria found the least common multiple of 6 and 15. her work is shown below. multiples of 6: 6, 12, 18, 24, 30, 36, 42, 48, 54, 60, . . multiples of 15: 15, 30, 45, 60, . . the least common multiple is 60. what is maria's error?

Which expressions equal 9 when x=4 and y=1/3 a. x2+6y b. 2x + 3y c. y2-21x d. 5 (x/2) -3y e. 3x-9y