The answer is: [D]: " 2.6 " .
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Given: a = - 2.6 ; What is the value of "-a "?
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So, what is the value of " - (-2.6)" ?
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The opposite of a negative is a positive;
so, " - (-2.6) = 2.6 " ; which is: "Answer choice: [D] " .
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Answer:
Part 1) 
Part 2) 
Step-by-step explanation:
we have

The cos(A) is negative, that means that the angle A in the triangle ABC is an obtuse angle and the value of the sin(A) is positive
The angle A lie on the II Quadrant
step 1
Find the measure of angle A

using a calculator

step 2
Find the sin(A)
we know that

substitute the value of cos(A)




step 3
Find tan(A)
we know that

substitute the values

Simplify

Answer:
Step-by-step explanation:
The formula for determining the sum of the first n terms of an arithmetic sequence is expressed as
Sn = n/2[2a + (n - 1)d]
Where
n represents the number of terms in the arithmetic sequence.
d represents the common difference of the terms in the arithmetic sequence.
a represents the first term of the arithmetic sequence.
If a = 5, the expression for the sum of the first 12 terms is
S12 = 12/2[2 × 5 + (12 - 1)d]
S12 = 6[10 + 11d]
S12 = 60 + 66d
Also, the expression for the sum of the first 3 terms is
S3 = 3/2[2 × 5 + (3 - 1)d]
S3 = 1.5[10 + 2d]
S3 = 15 + 3d
The sum of the first 12 terms is equal to ten times the sum of the first 3 terms. Therefore,
60 + 66d = 10(15 + 3d)
60 + 66d = 150 + 30d
66d + 30d = 150 - 60
36d = 90
d = 90/36
d = 2.5
For S20,
S20 = 20/2[2 × 5 + (20 - 1)2.5]
S20 = 10[10 + 47.5)
S20 = 10 × 57.5 = 575
Anything 5 and up, because when you multiply the by 15, they equal more than 65, making the inequality true.
Answer:that’s hard
Step-by-step explanation:nope
Nope