The lengths of the corresponding sides of two similar triangles are 10, 15, and 20 and 15, 22.5, and x: What is the value of x

x = 30

Step-by-step explanation:

10, 15, 20

15, 22.5, x

10 + (10÷2)

=10 + 5

= 15

15 + (15÷2)

=15 + 7.5

= 22.5

20 + (20÷2)

=20 + 10

= 30

Brielle will run the marathon faster.

Brielle = 104.8 minutes  

Joshua = 157.2 minutes

Step-by-step explanation:

Speed rate = distance /time

Brielle = 1.25 /10 = 0.125 miles per minute

Joshua = 1.5/18 = 0.083333 =1/12 miles per minute

Since 0.125 (Brielle) > 1/12 (Joshua)

Brielle will run the marathon faster.

To calculate the time that takes each one to run the entire race (13.1 miles)

Time= distance / speed

Feel free to ask for more if needed or if you did not understand something.