If the sum of their lengths is 5,520 miles then River D is 2360 and River C is 3160
7 x - 5 = 8
7 x = 8 + 5
7 x = 13
x = 13/7
7 ( 13/7) - 5 = 8
91/7 - 35/7 = 56/7
56/7 = 56/7 = 8
Answer:
1. 0.8 cm
2. 1.6 cm
Step-by-step explanation:
1.
The scale for 2nd map is 1 cm to 50 km, that means "1 cm on map" is "50 km in real life".
We already know distance from Cleveland to Cincinnati is 40 km, which is less than 50, so we know the distance on map would be less than 1 cm.
So we set up ratio and figure out (let x be distance on map from Cleveland to Cincinnati):

Hene, 0.8 centimeters would be the distance in 2nd map
2.
A scale of 1:50 means 1 cm equal 50 cm
So, 0.8m would be
0.8 * 100 = 80 cm
Hence, 80 cm would be represented by 80/50 on the map, that is:

That is 1.6 centimeters
The 9-sided polygon will have a central angle between the vertex and the center of one side of 360°/(2*9) = 20°. Then the apothem is
a = (6 in/2)*cot(20°) ≈ 8.242432 in
The perimeter is 9*6 in = 54 in, so the area is
A = (1/2)Pa = (1/2)*(54 in)*(8.242432 in) ≈ 222.5 in²