Answer:
D. is your answer
Step-by-step explanation:

Answer:
-1
Step-by-step explanation:
We need to find the value of tan² 70° -sec² 70°.
We know that,
...(1)
We can write the given expression as :
tan² 70° -sec² 70° = -(-tan² 70° +sec² 70°)
=-(sec² 70°-tan² 70°)
Using identity (1)
=-(1)
= -1
Hence, the value of the given expression is -1.
Answer:
5in
Step-by-step explanation:
You can find it by subtracting the side that has 15 in and the side that contains that 10 in. 15-10=5
To solve for the surface area of the pyramid, we make use
of the formula:
A= l w + l [sqrt ((w / 2)^2 + h^2)] + w [sqrt ((l / 2)^2 + h^2))
where,
l and w are the base of the pyramid = 100 mm
h is the height of the pyramid = 75 mm
Substituting the given values into the equation:
A= 100 * 100 + 100 [sqrt ((100 / 2)^2 + 75^2)] + 100 [sqrt ((100
/ 2)^2 + 75^2))
A = 10,000 + 100 (sqrt 2575) + 100 (sqrt 2575)
A = 20,148.90 mm^2
Therefore the surface area of the pyramid is about 20,149
mm^2.