What is the distance between (5, –1) and (3,7)?

2 Answers
Feb 10, 2016

Use the distance formula: d = sqrt((y_2-y_1)^2+(x_2-x_1)^2)

This yields a distance of sqrt 68 units.

Explanation:

Use d = sqrt((y_2-y_1)^2+(x_2-x_1)^2)

= sqrt((7-(-1))^2 +(3-5)^2) = sqrt(64+4) = sqrt 68

Feb 10, 2016

"distance exactly"=2sqrt(17)" "
"distance approximately"~= 8.25" to 2 decimal places"

Explanation:

Tony B

Now consider them as forming a triangle:
Tony B

From this you can see that Pythagoras will give us the answer for the distance between the points.

Let distance be d then

d^2 = (y_2-y_1)^2+(x_2-x_1)^2

so d = sqrt((-8)^2+(2)^2

so" " d= sqrt(68) = sqrt(2^2xx17)

=2sqrt(17)