Answer:
(I did the 2nd one first), , HL=21, EF=31
Step-by-step explanation:
FInd the midsegment of a trapezoid by adding the bases and dividing by two
(9x+3+5)/2=4x+7, now solve for x
9x+3+5=8x+14
x=6, so ef is 31
Do the first one the same way;
(2.5(12)+12)/2=HL
42/2=HL, HL=21
