Question 272094: Hi
I'm working with Isosceles triangles. I have (-9,-8) (-4,10)and (-4,-8)
I think this is an Isosceles because the lengths of 2 sides are the same. Is this correct?
Also, is the length of the base 5?
And lastly I need to figure out the area. I've been using the midpoint formula and am getting (-4,1) is this correct? I'm then using the 1st point and the midpoint to plug into the distance formula. I'm getting 106 under a square root sign.....Do I then use 10.29 to plug in the Area formula? I'm trying A= 1/2 (base)5 (height) 10.29=25.73...I don't think I'm supposed to end up with a decimal. Please help me find where I'm going wrong.
Thanks
Rachel
Found 2 solutions by Alan3354, dabanfield:
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! I'm working with Isosceles triangles. I have (-9,-8) (-4,10)and (-4,-8)
I think this is an Isosceles because the lengths of 2 sides are the same. Is this correct?
It's not isosceles, there are no 2 equal sides.
It is a right triangle.
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Also, is the length of the base 5?
The base is 5, from (-9,-8) to (-4,-8)
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And lastly I need to figure out the area. I've been using the midpoint formula and am getting (-4,1) is this correct? I'm then using the 1st point and the midpoint to plug into the distance formula. I'm getting 106 under a square root sign.....Do I then use 10.29 to plug in the Area formula? I'm trying A= 1/2 (base)5 (height) 10.29=25.73...I don't think I'm supposed to end up with a decimal. Please help me find where I'm going wrong.
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The area is bh/2 = 5*18/2 = 45 square units
Answer by dabanfield(803)  (Show Source):
You can put this solution on YOUR website! I'm working with Isosceles triangles. I have (-9,-8) (-4,10)and (-4,-8)
I think this is an Isosceles because the lengths of 2 sides are the same. Is this correct?
Also, is the length of the base 5?
And lastly I need to figure out the area. I've been using the midpoint formula and am getting (-4,1) is this correct? I'm then using the 1st point and the midpoint to plug into the distance formula. I'm getting 106 under a square root sign.....Do I then use 10.29 to plug in the Area formula? I'm trying A= 1/2 (base)5 (height) 10.29=25.73...I don't think I'm supposed to end up with a decimal. Please help me find where I'm going wrong.
Thanks
Rachel
0 solutions
Let's say point A is (-9,-8), B is (-4,-8) and C is (-4,10)
Side AB is sqrt((-8--8)^2 + (-4--9)^2) = sqrt(0^2 + 5^2) = 5
Side BC is sqrt((10--8)^2 + (-4--4)^2) = sqrt(18^2+0^2) = sqrt(18^2) = 18
Side AC is sqrt((10--8)^2 + (-4--9)^2) = sqrt(18^2+5^2) = sqrt(349)
The triangle is not isosceles :)
The area of the triangle is 1/2*base*height.
The base of this triangle is side AB and the height is BC. (notice that B and C both have an x-coordinate of -4 so BC is vertical. The points A and B have the same y-coordinate of -8 so AB is horizontal. AB and BC form a right angle).
The area then is 1/2*5*18 = 45
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