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Help me ill give 100 pts

Help me ill give 100 pts-example-1
User FirstName LastName
by
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2 Answers

15 votes
15 votes

Answer:

Small pizza is for 1 person, Large pizza is for 5 people

Skills needed: System of Equations

Explanation:

1) First, let's make two variables:

--> = how many people a large pizza can feed

--> = how many people a small pizza can feed

2) We need to use a system of equations to solve this --> A system is 2 or more equations with specific solutions for the variables involved.

Example:

-----------------

We can solve with elimination:

(Rewriting the first equation to look like the second one)

---> Then we add both:

When we add both equations, we eliminate the variable , solving for easily. After this, we can solve for

--->

--------------------------------------------------------------------------------------------------------------

This is the elimination method of a system (Note: we can also subtract equations if needed)

3) Let's make a system for this problem:

---> 3 small pizzas (multiplied by the number of people it can feed) + 2 large pizzas (multiplied by the number of people it can feed) is for 13 people.

---> 3 small pizzas (multiplied by the number of people it can feed) + 4 large pizzas (multiplied by the number of people it can feed) is for 23 people.

4) We have two equations:

We can eliminate by subtracting both equations.

--->

We subtracted from which is just 0 (so it does not have to be shown)

We subtracted from which is just

On the right side: subtracted from which is just

----> , divide by -2,

, which means a large pizza is for 5 people.

Substituting into the first equation (it does not matter which one you substitute into) will get

Small pizza is for 1 person.

User Andrey Korolyov
by
2.5k points
19 votes
19 votes

Answer:

Small pizza is for 1 person, Large pizza is for 5 people

Skills needed: System of Equations

Explanation:

1) First, let's make two variables:

-->
l = how many people a large pizza can feed

-->
s = how many people a small pizza can feed

2) We need to use a system of equations to solve this --> A system is 2 or more equations with specific solutions for the variables involved.

Example:


y=x+5


y+x=10

-----------------

We can solve with elimination:


y-x=5 \\ y+x=10

(Rewriting the first equation to look like the second one)

---> Then we add both:


y-x=5 \\ y+x=10 \\ 2y=15 \\ y= 7.5

When we add both equations, we eliminate the variable
x, solving for
y easily. After this, we can solve for

--->
y+x=10 \\ 7.5+x=10 \\ x=2.5

--------------------------------------------------------------------------------------------------------------

This is the elimination method of a system (Note: we can also subtract equations if needed)

3) Let's make a system for this problem:


3s+2l=13 ---> 3 small pizzas (multiplied by the number of people it can feed) + 2 large pizzas (multiplied by the number of people it can feed) is for 13 people.


3s+4l=23 ---> 3 small pizzas (multiplied by the number of people it can feed) + 4 large pizzas (multiplied by the number of people it can feed) is for 23 people.

4) We have two equations:


3s+2l=13 \\ 3s+4l=23

We can eliminate
s by subtracting both equations.

--->
3s+2l=13 \\ 3s+4l=23 \\ -2l=-10 \\ l=5

We subtracted
3s from
3s which is just 0 (so it does not have to be shown)

We subtracted
4l from
2l which is just
-2l

On the right side:
23 subtracted from
13 which is just
-10

---->
-2l=-10, divide by -2,
-10 / -2 = 5


l=5, which means a large pizza is for 5 people.


3s+2l=13 \\ 3s+2(5)=13 \\ 3s+10=13 \\ 3s=3 \\ s=1

Substituting
l into the first equation (it does not matter which one you substitute into) will get
s=1

Small pizza is for 1 person.

User Moz Morris
by
3.3k points