Answer:
see explanation
Step-by-step explanation:
Using the trigonometric identities
secx =
, cosecx = 
cotx =
, tanx = 
Consider the left side
secA cosecA - cotA
=
×
- 
=
- 
= 
=
( cancel sinA on numerator/ denominator )
= 
= tanA = right side ⇒ proven
9514 1404 393
Answer:
Step-by-step explanation:
The marked angles form a linear pair, so have a sum of 180°.
(4a +10) +(6a) = 180
10a = 170 . . . . . . . . . . subtract 10
a = 17 . . . . . . . . . . . . . divide by 10
__
Then the measure of angle ABC is ...
∠ABC = 4a +10 = 4(17) +10 = 68 +10 . . . . . substitute 17 for 'a'
∠ABC = 78°
A=1/2 (b1+b 2)(h) is the area of a trapezoid
15 x 15 = 175, that is how to find the square root.
1/4 - 1/3 = 3/12 - 4/12 = - 1/12