River C is 400 miles longer than River D. If the sum of their lengths is 5560 ​miles, what is the length of each​ river?

River D - 2580 miles

River C - 2980 miles

Step-by-step explanation:

Let the length of River D be represented with x

length of river C = 400 + x

total length of both rivers = 5560

x + 400 + x = 5560

2x + 400 = 5560

collect like terms

2x = 5560 - 400

2x = 5160

divide both sides of the equation by 2

x = 5160 / 2

x = 2580

length of river c = 400 + 2580 = 2980

last one.

step-by-step explanation:

last one.

generally speaking, the others follow some sort of pattern that correlates to either linear (looks like a straight line) or sinusoidal (looks like an s).

the last one is just a random cloud of points that doesn't correlate to any particular known order.

mr. flanders’ class sold 47 doughnuts and   mr. rodriquez’s class sold 38 cartons of milk

step-by-step explanation:

let x be the number of doughnuts sold by mr. flanders’ class and y be the number of cartons sold by mr. rodriquez’s class.

1. together, the classes sold 85 items, then

x+y=85.

2. both classes earn earned $104.49 for their school. if doughnuts were sold for $1.35 each, then x doughnuts costed $1.35x. if cartons of milk were sold for $1.08 each, then y cartons costed $1.08y. hence,

1.35x+1.08y=104.49.

3. solve the system of two equations: