0
$\begingroup$

In the right-angled triangle below, is it possible to find length $BC$ with only length $AC$ and angle $A$?

triangle rectangle

$\endgroup$
  • 1
    $\begingroup$ $BC=(AC)f(A)$, where $f$ is one of the basic trig functions. I'll leave you to work out which one. $\endgroup$ – David May 25 '18 at 1:36
  • $\begingroup$ "Triangle rectangle" was a new phrase to me. It makes perfect sense (at least once I see the picture), but it's more common in English to use the less latin-ified "right-angled triangle". $\endgroup$ – Arthur May 25 '18 at 1:58
  • $\begingroup$ Thanks, I translated literally I didn't know the english term. $\endgroup$ – Manspider May 25 '18 at 2:38
1
$\begingroup$

You know Angle A and side length AC therefore to find side length BC you can use trigonometry.

$\tan\theta = \frac O A$
$\tan A = \frac{BC}{AC}$
$BC=\tan A\times AC$

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.