# How do I find point D?

## Homework Statement

The problem:

 http://i.imgur.com/C5VwZ.png

## Homework Equations

So I got the constraints to be

1.x+y(less than or equal to) 275

2.225x+250y (less than or equal to) 63,000

3. x and y (Greater than) 0

So if the line from point A is extrapolated, then where it hits the x axis would be constraint 2 and point C is constraint 1.

## The Attempt at a Solution

The graph I ended up with:

 http://i.imgur.com/9jJYt.png

Last edited:

Mark44
Mentor

## Homework Statement

The problem:

 http://i.imgur.com/C5VwZ.png

## Homework Equations

So I got the constraints to be

1.x+y(less than or equal to) 275

2.225x+250y (less than or equal to) 63,000

3. x and y (Greater than) 0

So if the line from point A is extrapolated, then where it hits the x axis would be constraint 2 and point C is constraint 1.

## The Attempt at a Solution

The graph I ended up with:

 http://i.imgur.com/9jJYt.png

Point D is where the line x + y = 275 intersects with the line 225x + 250y = 63000. This is a simple matter of solving a system of two equations in two unknowns.

The problem you posted in your first link seems to have nothing to do with what you're doing here.

Whoops. Sorry about the wrong post.

When I set the two equal to each other. -x + 275 = (225/250)x + (63000/250) I'm getting the incorrect answer.

The book says it should be (230, 45)

I keep getting (12.1, 262.9)

Mark44
Mentor
Whoops. Sorry about the wrong post.

When I set the two equal to each other. -x + 275 = (225/250)x + (63000/250) I'm getting the incorrect answer.
You have a sign wrong in the right side. Solving the second equation for y gives y = -(225/250)x + 63000.

I get the right answer.
The book says it should be (230, 45)

I keep getting (12.1, 262.9)