Question

What is the measurement of BC?

Answer 1

Answer:

4.45

180 - 70 - 90 = 20

By Law of Sines

13/sin90 = BC/sin20

BC = 4.45

Sin90 = 1

Answer 2

Answer:

             $BC=4.42$

Step-by-step explanation:

In, given figure:

        AB=13

        ∠B=70°

we have to find BC ?

as,      

              $cosA=\frac{Base}{Hypotenuse}$

Given cos(70°)≈0.34

                     cos(70°)   $=\frac{BC}{AB}$

               

                        $0.34=\frac{BC}{13}\\\\ BC=0.34*13\\\\BC=4.42$

The measurement of BC is

             $BC=4.42$