Pls explain and will mark as brainliest

x = -5

Step-by-step explanation: The green x's represent positive x's, the yellow 1s represent positive numbers, and the red 1s represent negative numbers. So if you count everything your equation should look like 5x + 4 = -21. First you want to do the opposite of the plus 4, which is subtracting 4. That way the x is by itself on the left side of the equal sign. But what you do to one side you have to do to the other. So then you subtract 4 from -21. But because 21 is already negative it would equal -25. Now your equation should look like 5x = -25. Just divide by 5 for both sides and your x equals -5.

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: