Question

Which of the following sums would be under the radical symbol to find the distance between the points (7, -1) and (-8, -9)?


1^2 + 10^2

1^2 + 8^2

15^2 + 8^2

Answer 1

\[\Large\bf\sf (\color{#8C3D62}{x_1},\;\color{#F35633}{y_1})=(\color{#8C3D62}{7},\;\color{#F35633}{-1}),\qquad\qquad (\color{royalblue}{x_2},\;\color{#CC0033}{y_2})=(\color{royalblue}{-8},\;\color{#CC0033}{-9})\]
Here is our distance formula:
\[\Large\bf\sf d\quad=\quad \sqrt{(\color{royalblue}{x_2}-\color{#8C3D62}{x_1})^2+(\color{#CC0033}{y_2}-\color{#F35633}{y_1})^2}\]Understand how to plug the values in?
Match up the colors! :)

Answer 2

It's x1-x2 and y1-y2 though

Answer 3

We're squaring the quantities, so it won't matter.
(x2-x1) is simply the negative of (x1-x2).

And when we square it, the negative goes away.

But ya if you remember the formula with x1 first, then my bad ^^
might look a little confusing.

Answer 4

Lol yeah.. I've tried setting it up, but I didn't understand the answer

Answer 5

\[\Large\bf\sf d\quad=\quad \sqrt{(\color{royalblue}{x_2}-\color{#8C3D62}{x_1})^2+(\color{#CC0033}{y_2}-\color{#F35633}{y_1})^2}\]Plug in the numbers!! +_+\[\Large\bf\sf d\quad=\quad \sqrt{(\color{royalblue}{-8}-\color{#8C3D62}{7})^2+(\color{#CC0033}{-9}-(\color{#F35633}{-1}))^2}\]

Answer 6

understand how to deal with the -(-1)?

Answer 7

Turn it into a positive 1?

Answer 8

Is the answer 1^2+8^2 ?

Answer 9

Your second value looks good, 8^2.
You added the 1 to -9, gives you (-8)^2 which is 8^2. Good good.

Answer 10

The first value is -8-7.
That does not give us 1 or negative 1.
Hmmmm check your subtraction again! :O

Answer 11

Can you help me with this one too?

Find the distance between the points (2.7, 5.1) and (3, 4.7).


0.05

0.5

5

Answer 12

\[\Large\bf\sf d\quad=\quad \sqrt{(\color{royalblue}{3}-\color{#8C3D62}{2.7})^2+(\color{#CC0033}{4.7}-\color{#F35633}{5.1})^2}\]

Answer 13

Simplifyyyy \c:/
What do you get for your squares?