You seem to have several right ideas, but not have put them together correctly.I tried finding the height of the triangle first in terms of r, but not sure how to find the base. Or is there a different way to approach this? Thanks for guidance.
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it is mentioned that the triangle is isosceles, but am I allowed to assume that the angle at B is right-angle?You seem to have several right ideas, but not have put them together correctly.
First, you know what kind of triangle this is, right? If you know the height, you also know the base. Your mention of [imath]100\sqrt{2}[/imath] implies you have thought of these ideas (though I don't think it will be useful in itself).
Second, your drawing doesn't show the bottom circle touching the base of the triangle, so some of your thinking is wrong.
Use this:
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No, you can't just assume; but you can conclude it based on a reason.it is mentioned that the triangle is isosceles, but am I allowed to assume that the angle at B is right-angle?
I am not sure about the value of [imath]100\sqrt{2}[/imath] since can't tell if it is right angle. I got that value "assuming" that triangle is half a square, but is that allowed?
I realise that the height of the triangle now is [imath]3\sqrt{2}(r)[/imath] + r, because there is no space after the bottom circle
If it's a right isosceles triangle, then ...I am tickled with "if you know the height, then you know the base"
how?
Equivalently, the altitude is 100, and you can just solve (3sqrt(2)+1)r = 100. Your answer is correct.Please check if my calculations are correct.
for the base of the triangle I have 200
for the height I have 3sqrt(2)r + r
equating the area of the triangle to 10000, and solving for r as the subject, I have (rounded to the nearest unit) 19 unit as the answer
ah yes that's a different way of looking at it too! thanks so much for the help, sorry I ask a lot, I am not the brightest but really want to understand how things work mathematically!Equivalently, the altitude is 100, and you can just solve (3sqrt(2)+1)r = 100. Your answer is correct.