Answer: 21
=================================================================
Work Shown:
The diagram shows that JK = 12 and GF = 2.5*(JK) = 2.5*12 = 30
The midsegment HL will be the average of the two lengths it is parallel to.
We'll add up the values and then cut the result in half
HL = (JK+GF)/2
HL = (12+30)/2
HL = 42/2
HL = 21
