In right triangle RST, angle T is the right angle, RT = 20... | SAT Right triangles and trigonometry Question, Answer Explained

SAT Owl

Question bank / Right triangles and trigonometry

Math · Geometry and TrigonometryEasy

In right triangle $RST$ , angle $T$ is the right angle, $RT = 20$ , and $ST = 21$ . What is the value of $\tan R$ ?

$\frac{20}{21}$

$\frac{21}{20}$

$\frac{20}{29}$

$\frac{21}{29}$

Show answer and explanation

Answer: B

For angle $R$ , the opposite leg is $\overline{ST}$ and the adjacent leg is $\overline{RT}$ . So $\tan R = \frac{\text{opposite}}{\text{adjacent}} = \frac{ST}{RT} = \frac{21}{20}$ .

Choice A is $\tan S$ , because it puts the leg adjacent to angle $R$ in the numerator.

Why the other choices are wrong

A. This is adjacent over opposite, which is tan S.
C. 20/29 is adjacent over hypotenuse, cos R.
D. 21/29 is opposite over hypotenuse, sin R.

Ask Owl about this question Next question

Got it wrong? On SAT Owl, Owl looks at the answer you chose and explains the exact mistake, then gives you similar questions until it sticks. Get your predicted SAT score free, or take a free full-length practice test.