Trigonometry - Finding degrees of triangle

AI Thread Summary
To find the area of triangle AST, it's important to first determine the right angle in triangle ART, which is right-angled. Given the sides AR = 12, AS = 13, and AT = 37, the Pythagorean theorem can be applied to find the third side of triangle ARS. Assumptions about angles, such as RAS and SAT being 45 degrees, are not valid without proof. The area of triangle AST can be calculated using the formula A = (1/2) * AH * BC, where AH is the altitude. Understanding these principles is crucial for solving the problem accurately.
BrownPrincezz
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I'm having problem with this question:

From a point A, three straight lines are drawn to points R, S, T so that TRIANGLE ART is right-angled and points R , S, T are collinear. If AR = 12, AS=13, AT=37, determine the area of TRIANGLE AST.


Is it ok to assume RAS and SAT is 45 degrees?
 
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BrownPrincezz said:

Is it ok to assume RAS and SAT is 45 degrees?


no. your given 2 sides of triangle ARS find the 3rd side. then notice triangle ART. notice what you're given and determine your goal. :smile:
 
BrownPrincezz said:
I'm having problem with this question:

From a point A, three straight lines are drawn to points R, S, T so that TRIANGLE ART is right-angled and points R , S, T are collinear. If AR = 12, AS=13, AT=37, determine the area of TRIANGLE AST.


Is it ok to assume RAS and SAT is 45 degrees?


No, of course, you cannot assume things in mathematics. Everything has to be proven.
Ok AR = 12, AS = 13, and AT = 37, so AR is the smallest of the three.
So if ART is a right triangle, what should be the right angle, then, is it andle A, R, or T?
Knowing the right angle, one can use the Pythagorean theorem, ie: a2 + b2 = c2, where c is the length of the hypotenuse in a right triangle.
You should note that, the area of an triangle ABC can be calculated by:
A = (1 / 2) AH x BC, there AH is its altitude.
Can you go from here? :)
 
VietDao29 said:
No, of course, you cannot assume things in mathematics. Everything has to be proven.
Ok AR = 12, AS = 13, and AT = 37, so AR is the smallest of the three.
So if ART is a right triangle, what should be the right angle, then, is it andle A, R, or T?
Knowing the right angle, one can use the Pythagorean theorem, ie: a2 + b2 = c2, where c is the length of the hypotenuse in a right triangle.
You should note that, the area of an triangle ABC can be calculated by:
A = (1 / 2) AH x BC, there AH is its altitude.
Can you go from here? :)

Thank you guys so much :)
That was very helpful
 
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