Geometry homework help???

Question

Please EXPLAIN the steps because i want to understand it.

The vertices of a triangle are located at X(-2,-1), Y(2.5), and Z(4,3). What is the perimeter of his triangle? Round to the nearest tenth.

Answer 1

easiest would be to draw the points on a graph.

Then use the distance formula:

√[(x1-x2)^2 + (y1-y2)^2]

XY= √[(-2-2)^2 + (-1-5)^2] = √[16 + 36] = 7.2

YZ= √[(2-4)^2 + (5-3)^2] = √[4 + 4] = 2.8

XZ= √[(-2-4)^2 + (-1-3)^2] = √[36 + 16] = 7.2

Perimeter = XY + YZ + XZ = 7.2+2.8+7.2 = 17.2 units

Answer 2

Hi,

Find the lengths of all 3 sides using the distance formula.

....... __________________

D = √(x2 - x1)² + (y2 - y1)²

X(-2,-1) and Y(2,5) then

......... _______________

XY = √(-2 - 2)² + (-1 - 5)²

......... _________

XY = √(-4)² + (-6)²

......... ______

XY = √16 + 36

......... __

XY = √52

.........  .__

XY = 2√13

Y(2,5) and Z(4,3), then

......... ______________

YZ = √(2 - 4)² + (5 - 3)²

......... _________

YZ = √(-2)² + (2)²

......... _____

YZ = √4 + 4

......... _

YZ = √8

........... _

YZ = 2√2

X(-2,-1) and Z(4,3), then

......... ______________

XZ = √(-2 - 4)² + (-1 - 3)²

......... _________

XZ = √(-6)² + (-4)²

......... _______

XZ = √36 + 16

......... __

XZ = √52

........... __

XZ = 2√13

The perimeter is √52 + √8 + √52 =  7.21 + 2.83 + 7.21 = 17.25

The perimeter is 17.3 to the nearest tenth. <==ANSWER

I hope that helps!! :-)

Answer 3

ok uso u want to find the total distance around the triangle

so u want to use the distance formula which comes from pythagorus orginally.

distance from one point to the next  = √(change in x coords)^2 + (change in y coords)^2

do that 3 times with yr points and them total up the distance

Answer 4

Ok, I have NOT learned this yet

But I know it I am so smart!! :)

Find the lengths of all 3 sides using the distance formula.

....... __________________

D = √(x2 - x1)² + (y2 - y1)²

X(-2,-1) and Y(2,5) then

......... _______________

XY = √(-2 - 2)² + (-1 - 5)²

......... _________

XY = √(-4)² + (-6)²

......... ______

XY = √16 + 36

......... __

XY = √52

......... .__

XY = 2√13

Y(2,5) and Z(4,3), then

......... ______________

YZ = √(2 - 4)² + (5 - 3)²

......... _________

YZ = √(-2)² + (2)²

......... _____

YZ = √4 + 4

......... _

YZ = √8

........... _

YZ = 2√2

X(-2,-1) and Z(4,3), then

......... ______________

XZ = √(-2 - 4)² + (-1 - 3)²

......... _________

XZ = √(-6)² + (-4)²

......... _______

XZ = √36 + 16

......... __

XZ = √52

........... __

XZ = 2√13

The perimeter is √52 + √8 + √52 = 7.21 + 2.83 + 7.21 = 17.25

The perimeter is 17.3 to the nearest tenth

17.3 to the nearset tenth is the anwser. Oh, and is't this considerd cheating???