Answer:
Perimeter is 17.07
Step-by-step explanation:
We know that DF = EF = 5 cm, since D and E are the midpoints of AC and AB, both of which are 10 cm in length.
We need to use the Pythagorean theorem to get the length of DE.

So the perimeter of DEF is 5 + 5 + 7.07 = 17.07
Answer:
Step-by-step explanation:
2. 9a +4c=43
a+c=7
The total tickets for adults and children = 7 (a+c =7) 7 people in all
price for adult = $9 (9a) Price per child =$4 (4c)
total price =$ 43
9a +7c = 43
Lucy packs plates faster she packs 5 plates every minute. Mike packs 4 plates every minute because 3/4 of an hour is 45 minutes, then you divide 180 by 45 and the answer is 4 per minute.
Franco would have to pack 90 plates every 20 minutes (1/3 of an hour) for his rate to be between Lucy's and Mike's. Lucy's rate is at 100 plates per 20 minutes because she can pack 5 plates every minute. Mike's it's at 80 plates per 20 minutes because he can pack 4 plates per minute. So that means that For Franco to be in the middle he has to pack 90 Plates every 20 minutes.
Hope this helps!!!
Answer:
12
Step-by-step explanation:
Use pythag to solve.
x^2+5^2=13^2
x=12