Question

in the right triangle shown, angle A=30 and AC=18 how long is AB?

Answer 1

Answer:

$AB=9\sqrt{3}\ units$

Step-by-step explanation:

see the attached figure to better understand the problem

we know that

In the right triangle ABC

The cosine of angle of 30 degrees is equal to divide the adjacent side to angle of 30 degrees by the hypotenuse

so

$cos(30^o)=\frac{AB}{AC}$

we have

$cos(30^o)=\frac{\sqrt{3}}{2}$

$AC=18\ units$

substitute

$\frac{\sqrt{3}}{2}=\frac{AB}{18}$

solve for AB

$AB=(18)\frac{\sqrt{3}}{2}$

$AB=9\sqrt{3}\ units$

Answer 2

Answer:

T

Step-by-step explanation: