Answer:
see explanation
Step-by-step explanation:
The sum of the 3 angles in a triangle = 180°
Subtract the sum of the given angles from 180 for B
B = 180° - (90 + 40)° = 180° - 130° = 150°
--------------------------------------------------------------
sin40° =
= 
Multiply both sides by 21
21 × sin40° = a, thus
a ≈ 13.5 ( to the nearest tenth )
--------------------------------------------------------------
cos40° =
= 
Multiply both sides by 21
21 × cos40° = b, thus
b ≈ 16.1 ( to the nearest tenth )
Solution:
Vertical angles are a pair of opposite angles formed by intersecting lines. re vertical angles. Vertical angles are always congruent.
These two angles (140° and 40°) are Supplementary Angles because they add up to 180°:
Notice that together they make a straight angle.
Hence,
From the image
The following pairs form vertical angles

Hence,
One pair of the vertical angles is ∠1 and ∠3
Part B:
Two angles are said to be supplementary when they ad together to give 180°
Hence,
From the image,
The following pairs are supplementary angles

Hence,
One pair of supplementary angles is ∠5 and ∠6
12n = 3-5n-1 or n =3-5n-1???
The length of each leg is 6
is proved
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Solution:</u></h3>
Given that,
------- (1)
First we will simplify the LHS and then compare it with RHS
------ (2)

Substitute this in eqn (2)

On simplification we get,


Cancelling the common terms (sinx + cosx)

We know secant is inverse of cosine

Thus L.H.S = R.H.S
Hence proved