What is the distance between (-7, 7) and (5, 6) ?

1 Answer
Feb 10, 2017

The distance between the two points is:

sqrt(145)~~12.04 to 2 decimal places.

Explanation:

When you are not sure of something make a quick sketch so you can see more clearly what the situation is.

Tony B

Let point 1 be P_1->(x_1,y_1)=(-7,7)
Let point 2 be P_2->(x_2,y_2)=(5,6)
Let the direct distance between the two points be d

The change in down is: ""y_2-y_1" "=" "7-6" "=" "1
The change in along is: ""x_2-x_1" "=" "5-(-7)" "=" " 12

Using Pythagoras d^2=12^2+1^2

d=sqrt(145)

The only factors of 145 are 1, 5, 9, 145,

So we can not break this down into simplified surds (roots)

So we represent the solution as sqrt(145) which is an exact value or as a rounded decimal which is not exact.

=> d= sqrt(145)~~12.04 to 2 decimal places.

The sign of ~~ means approximately