16 cm - 2.5 cm = 13.5 cm, which is 1/4 of the diameter of the large gear. Take 13.5 cm * 4, and you have the diameter of the large gear, which is 54 cm.
A negative times a negative is a positive so...
( - ) ( - ) ( - ) ( -10x ) = -5
10x = -5
x = -5/10
x = -1/2
Hello!
I have all the work but I do not know how to post it on here.
The area of the figure shown is 57.
I hope it helps!