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Comment on Area of triangle
Do we even need the quadratic
Given your answer, it looks like I did something wrong. Am I not allowed to assume that all isoscoles triangles can be broken into two 30-60-90 triangles?
No, we can't assume that the
No, we can't assume that the height of an isosceles triangle will create two 30-60-90 triangles. This assumes that the two equal angles are both either 60 degree or 30 degrees, but there are infinitely many different isosceles triangles.
Consider, for example, an isosceles triangle with angles 5, 5 and 170 degrees. If you divide that triangle into two equal triangles, their angle measurements will be 5, 85 and 90 degrees
Hi Brent, in this question
Please clarify.
If we divide triangle ABC
If we divide triangle ABC into two right triangles, then EACH right triangle has area 6 (not 12)
At 1:34 in the above video, we see that our purple right triangle has a base of 3 and a height of 4.
Area = (base)(height)/2
= (3)(4)/2
= 6
So, the area of triangle ABC = 2(6) = 12
Does that help?
Cheers,
Brent
Why can we assume that the
Great question!
Great question!
In the official guide, the GMAT test takers provide the following definition of an isosceles triangle:
An isosceles triangle has AT LEAST two sides of the same length.
So, we can say that an equilateral triangle is a special type of isosceles triangle (in the same way we can say a square is a special type of rectangle)