Need help solving this system of equations please

S

sarahilc

New member
Joined
Feb 3, 2011
Messages
15
The full question is:
In order to increase sales, a shopkeeper mixes two types of candies: peppermints and cinnamon candies. The peppermints sell for $1.80/kg. The cinnamon candy sells for 2.40/kg. The new candy mixture sells for 2.16/kg. The shopkeeper makes up 50 kg of the new mixture. Use a graph to determine the amount of each type of candy that is needed to make the new mixture. Verify your answer.

And then I'm suppose to use Geo Sketchpad or my graphing calculator to solve.
I don't know how I would go about solving it with a graph right off the bat,
but I figure it starts something like this:

x+y=50
1.80x+2.40y=2.16 (50) ?
or something like that...
I really don't know though.
 
sarahilc said:
The full question is:
In order to increase sales, a shopkeeper mixes two types of candies: peppermints and cinnamon candies. The peppermints sell for $1.80/kg. The cinnamon candy sells for 2.40/kg. The new candy mixture sells for 2.16/kg. The shopkeeper makes up 50 kg of the new mixture. Use a graph to determine the amount of each type of candy that is needed to make the new mixture. Verify your answer.

And then I'm suppose to use Geo Sketchpad or my graphing calculator to solve.
I don't know how I would go about solving it with a graph right off the bat,
but I figure it starts something like this:

To solve with a graph, you plot the equations - the point of intersection gives you the solution.

x+y=50 <<<< What are 'x' & 'y'?

1.80x+2.40y=2.16 (50) ?
or something like that...
I really don't know though.
Click to expand...
 
x=peppermint, y=cinnamon candies... (?)
I don't know how to plot the equation.
 
Hello, sarahilc!

In order to increase sales, a shopkeeper mixes two types of candies: peppermints and cinnamon candies.
The peppermints sell for $1.80/kg. The cinnamon candy sells for 2.40/kg. The new candy mixture sells for 2.16/kg.
The shopkeeper makes up 50 kg of the new mixture.
Use a graph to determine the amount of each type of candy that is needed to make the new mixture.
Verify your answer.

And then I'm suppose to use Geo Sketchpad or my graphing calculator to solve.
I don't know how I would go about solving it with a graph right off the bat,
but I figure it starts something like this:

. . \(\displaystyle x+y\:=\:50\)
. . \(\displaystyle 1.80x+2.40y\:=\:2.16 (50)\) . This is correct!
Click to expand...

The first equation becomes: .\(\displaystyle y \:=\:-x + 50\)

The second simplifies to: .\(\displaystyle y \:=\:-\tfrac{3}{4}x + 45\)

Now graph those line and determine their intersection.

 
You must log in or register to reply here.
Top