Question

Anyone able to help with this question?

Answer 1

Answer:

This is trigonomentry

Use SOHCAHTOA

where :

s is sin

c is cos

t is tan

o is opposite (side)

h is hypotenuse (opposite of 90 degree angle)

and a is adjacent (side)

Sin = o/h

cos = a/h

tan = o/a

in this case we are looking for side BC which is the hypotenuse(h)

and we have the side adjacent(a) to angle 71

since we have a and h determine what to use SIN, COS, OR TAN?

we should use Cos

they‘ve given the angle so we should do this...

Cos71 = $\frac{6.3}{h}$

Cos71 = $\frac{6.3}{BC}$

now apply algebra...

6.3/cos71= BC

BC= 19.3507869666

BC = 19.4   (3SF)