Question

Pls help:Find all the missing elements:

Answer 1

Answer:

B = 48.7° , C = 61.3° , b = 12

Step-by-step explanation:

In order to find B we must first angle C

To find angle C we use the sine rule

That's

$\frac{ |a| }{ \sin(A) } = \frac{ |c| }{ \sin(C) }$

From the question

a = 15

A = 70°

c = 14

So we have

$\frac{15}{ \sin(70) } = \frac{14}{ \sin(C) }$

$\sin(C) = \frac{14 \sin(7 0 ) }{15}$

$C = \sin^{ - 1} ( \frac{14 \sin(70) }{15} )$

C = 61.288

C = 61.3° to the nearest tenth

Since we've found C we can use it to find B.

Angles in a triangle add up to 180°

To find B add A and C and subtract it from 180°

That's

A + B + C = 180

B = 180 - A - C

B = 180 - 70 - 61.3

B = 48.7° to the nearest tenth

To find b we can use the sine rule

That's

$\frac{ |a| }{ \sin(A) } = \frac{ |a| }{ \sin(B) }$

$\frac{15}{ \sin(70) } = \frac{ |b| }{ \sin(48.7) }$

$|b| = \frac{15 \sin(48.7) }{ \sin(70) }$

b = 11.9921

b = 12.0 to the nearest tenth

Hope this helps you