50 added to three times an unknown number equals -11?

Hello there!

An equation to model this situation is 3n - 50 = -11

The unknown number has a value of 13.

Okay, so let's start by breaking down the question - we'll use n to model the unknown number.

-50 added to three times an unknown number equals -11?

This means we are adding -50 to something else. (We can use + -50 or - 50 since they are the same thing, I'll use - 50 since it's easier to follow.)

-50 added to three times an unknown number equals -11?

This phrase can be modeled as 3n. This is what we are taking 50 from, so we can add that to the end of the equation so far.

3n - 50

-50 added to three times an unknown number equals -11?

This can means the equation equals -11. We can model it as = -11. Now, let's add it to our equation.

3n - 50 = -11

Now, solve for n.

You want to start by canceling -50 out on the left side, so n is on it's own side, and to do this you add 50 to both sides.  

3n - 50 + 50 = -11 + 50

3n = 39

To finish isolating n, divide both sides of the equation by 3.

3÷3n = 39÷3

n = 13.

I hope this helps and have a great day!

4

step-by-step explanation:

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: