Question

Darko found the distance between points A(3,-4) and B(-1,3) his work is shown below

Answer 1

Darko has done a mistake in step 1. which putting the values of y coordinates of A and B in the formula.

Explanation:

Distance between the two points is calculated by the formula

d =
`\sqrt{(x-x')^(2)+(y-y')^(2)}`

Since coordinates of the two points have been given as A(3, -4) and B(-1, 3).

Therefore, we can calculate the distance between these points by plugging in the values.

Distance AB =
`\sqrt{(-3-1)^(2)+(3+4)^(2)}`

=
`\sqrt{(-4)^(2)+(7)^(2)}`

=
`√(16+49)`

=
`√(65)`

= 8.06 unit

Darko has made a mistake while replacing the values in the formula in step 1.

Answer 2

In this question , Darko have to find the distance between A(3,-4) and B (-1,3) .

He uses the correct formula, which is

`d = \sqrt{ (x_(2) - x_(1))^2 + (y_(2) - y_(1))^2}`

And on substituting the values , we will get

`d = √( (-1-3)^2 + (3- (-4))^2 )`

And in this line, Darko did the mistake .