From the diagram below , x = t ( r - h ) / h
<h3>Further explanation</h3>
Firstly , let us learn about trigonometry in mathematics.
Suppose the ΔABC is a right triangle and ∠A is 90°.
<h3>sin ∠A = opposite / hypotenuse</h3><h3>cos ∠A = adjacent / hypotenuse</h3><h3>tan ∠A = opposite / adjacent </h3>
There are several trigonometric identities that need to be recalled, i.e.
![cosec ~ A = \frac{1}{sin ~ A}](https://tex.z-dn.net/?f=cosec%20~%20A%20%3D%20%5Cfrac%7B1%7D%7Bsin%20~%20A%7D)
![sec ~ A = \frac{1}{cos ~ A}](https://tex.z-dn.net/?f=sec%20~%20A%20%3D%20%5Cfrac%7B1%7D%7Bcos%20~%20A%7D)
![cot ~ A = \frac{1}{tan ~ A}](https://tex.z-dn.net/?f=cot%20~%20A%20%3D%20%5Cfrac%7B1%7D%7Btan%20~%20A%7D)
![tan ~ A = \frac{sin ~ A}{cos ~ A}](https://tex.z-dn.net/?f=tan%20~%20A%20%3D%20%5Cfrac%7Bsin%20~%20A%7D%7Bcos%20~%20A%7D)
Let us now tackle the problem!
Look at ΔADE in the attachment.
We will use the following formula to find relationship between variable t and h:
tan ∠A = opposite / adjacent
![\tan \angle A = \frac{DE}{AD}](https://tex.z-dn.net/?f=%5Ctan%20%5Cangle%20A%20%3D%20%5Cfrac%7BDE%7D%7BAD%7D)
→ Equation 1
Look at ΔABC in the attachment.
We will use the following formula to find relationship between variable r , t and x:
tan ∠A = opposite / adjacent
![\tan \angle A = \frac{BC}{AB}](https://tex.z-dn.net/?f=%5Ctan%20%5Cangle%20A%20%3D%20%5Cfrac%7BBC%7D%7BAB%7D)
→ Equation 2
Next we can substitute equation 1 to equation 2 :
![\tan \angle A = \frac{r}{x+t}](https://tex.z-dn.net/?f=%5Ctan%20%5Cangle%20A%20%3D%20%5Cfrac%7Br%7D%7Bx%2Bt%7D)
![\frac{h}{t} = \frac{r}{x+t}](https://tex.z-dn.net/?f=%5Cfrac%7Bh%7D%7Bt%7D%20%3D%20%5Cfrac%7Br%7D%7Bx%2Bt%7D)
![(x + t)h = r ~ t](https://tex.z-dn.net/?f=%28x%20%2B%20t%29h%20%3D%20r%20~%20t)
![(x + t) = \frac{(r ~ t)}{h}](https://tex.z-dn.net/?f=%28x%20%2B%20t%29%20%3D%20%5Cfrac%7B%28r%20~%20t%29%7D%7Bh%7D)
![x = \frac{(r ~ t)}{h} - t](https://tex.z-dn.net/?f=x%20%3D%20%5Cfrac%7B%28r%20~%20t%29%7D%7Bh%7D%20-%20t)
![x = \frac{(r ~ t)}{h} - \frac{(h ~ t)}{h}](https://tex.z-dn.net/?f=x%20%3D%20%5Cfrac%7B%28r%20~%20t%29%7D%7Bh%7D%20-%20%5Cfrac%7B%28h%20~%20t%29%7D%7Bh%7D)
![\large {\boxed {x = \frac{t(r - h)}{h}} }](https://tex.z-dn.net/?f=%5Clarge%20%7B%5Cboxed%20%7Bx%20%3D%20%5Cfrac%7Bt%28r%20-%20h%29%7D%7Bh%7D%7D%20%7D)
<h3>Learn more</h3>
<h3>Answer details</h3>
Grade: College
Subject: Mathematics
Chapter: Trigonometry
Keywords: Sine , Cosine , Tangent , Opposite , Adjacent , Hypotenuse , Triangle , Fraction , Lowest , Function , Angle