Answer:
A) 220.5 mm^2
Step-by-step explanation:
<u>Explanation</u>:-
Given A regular triangular pyramid has a base of area is 31.5mm^2
and also given surface area of triangular pyramid is 252 mm ^2
by using formula
surface area of regular triangular pyramid = base of area + half of lateral surface.

252 = 31.5 + 

220.5 = lateral area of triangular pyramid
lateral area of triangular pyramid = 220.5 mm^2
Answer:
the letter " a " because uts just making the sentence a run on
Answer: "...in descending order."
There you go.
Answer:
See explanation
Step-by-step explanation:
The given trigonometric equation is
.
We take the inverse cosine of both sides to get:

to the nearest degree
None of the options satisfies the given equation.
But if the question is actually;

Then;
.
.
.
.
Or
.
In this case the answer will be B
Answer:
The answer to your question is: ∠K = 138°
Step-by-step explanation:
m∠N = 42°
m∠K = ?
The sum of all the internal angles in a quadrangle equals 360°
then
∠N + ∠L + ∠M + ∠K = 360°
∠N = ∠ L and ∠M = ∠K
So, 2 ∠N + 2 ∠K = 360
Substitution
2 (42) + 2 ∠K = 360
84 + 2 ∠K = 360
2 ∠K = 360 - 84
2 ∠K = 276
∠K = 276 / 2
∠K = 138°