# Distance on a Graph

• Oct 11th 2006, 12:06 PM
Yppolitia
Distance on a Graph
Ok, so in my class we are doing about distances on a graph. I have a question asking which point is closer to (0,0):
(3,2)
(4,8)
or
(10,7)

So I did this. I first went to work out (0,0) and (3,2).

I know you have to subtract the X co ordinates to find the distance from them and then the same for Y co ordinates.

0-3=-3 (then square) -3^2=9
0-2=-2 (then square) -2^2=4 (plus answers together) = 13 = (sqrt)13

Now my homework paper says not to use a calculator so I assume im suppose to leave it here or just say its roughly 4?

Did I calculate this right?
• Oct 11th 2006, 12:11 PM
ThePerfectHacker
Quote:

Originally Posted by Yppolitia
Ok, so in my class we are doing about distances on a graph. I have a question asking which point is closer to (0,0):
(3,2)
(4,8)
or
(10,7)

So I did this. I first went to work out (0,0) and (3,2).

I know you have to subtract the X co ordinates to find the distance from them and then the same for Y co ordinates.

0-3=-3 (then square) -3^2=9
0-2=-2 (then square) -2^2=4 (plus answers together) = 13 = (sqrt)13

Now my homework paper says not to use a calculator so I assume im suppose to leave it here or just say its roughly 4?

Did I calculate this right?

When you have a square root. Square both of them and which is bigger was the number bigger initially.

For example,
What is larger sqrt(5) or 3sqrt(2)
Square each one,
5 and 9*2=18
Since 18>5
We conclude that,
sqrt(5)<3sqrt(2)