Question 86259
<pre>Would someone please help me with this problem. The directions are to use the
Pythagorean theorem to determine the length of each line segment. Where
appropriate, round to the nearest hundredth. The points on a graph of the line
in question are (1,-1) and (3,2). Thank you.
<b>
Let's plot those points and draw the line segment:

{{{drawing(400,250,-4,4,-2,3, graph(400,250,-4,4,-2,3), line(1,-1,3,2),

locate (3.3,2.4,"(3,2)"), locate(.3,-1.2,"(1,-1)")

) }}}

Start at the bottom point of the line segment and draw a horizontal 
segment just long enough to reach to a point directly underneath the
top point.

{{{drawing(400,250,-4,4,-2,3, graph(400,250,-4,4,-2,3), line(1,-1,3,2),

locate (3.3,2.4,"(3,2)"), locate(.3,-1.2,"(1,-1)"), line(1,-1,3,-1) ) }}}

Now draw a vertical line from the end of that horizontal segment to the
top point:

{{{drawing(400,250,-4,4,-2,3, graph(400,250,-4,4,-2,3), line(1,-1,3,2),

locate (3.3,2.4,"(3,2)"), locate(.3,-1.2,"(1,-1)"), line(1,-1,3,-1), line(3,-1,3,2)
) }}}

Label the sides of that right triangle a, b and c so that c is the
hypotenuse, whose length will be the distance between the two given
points.


{{{drawing(400,250,-4,4,-2,3, graph(400,250,-4,4,-2,3), line(1,-1,3,2),

locate (3.3,2.4,"(3,2)"), locate(.3,-1.2,"(1,-1)"), line(1,-1,3,-1), line(3,-1,3,2), locate(2,-1,"a"), locate(3.1,.5,"b"), locate(1.5,.6,"c") 
) }}}

Now if you will think of the x-axis as a ruler. you can see 
that side "a" is 2 units long. Similarly, if you will think 
of the y-axis as a ruler. you can see that side "b" is 3 units 
long.

{{{drawing(400,250,-4,4,-2,3, graph(400,250,-4,4,-2,3), line(1,-1,3,2),
locate (3.3,2.4,"(3,2)"), locate(.3,-1.2,"(1,-1)"), line(1,-1,3,-1), line(3,-1,3,2), locate(2,-1,"a = 2"), locate(3.1,.5,"b = 3"), locate(1.5,.6,"c") 
) }}}

Now we use the Pythagorean theorm to calculate c:

c² = a² + b²

c² = 2² + 3²

c² = 4 + 9

c² = 13

Taking square roots:

c = {{{sqrt(13)}}} = 3.605551275 or about 3.61 units long,
rounded to hundredths.

Edwin</pre>