Answer:
Jenna is correct.
Step-by-step explanation:
See attached image.
The best deal would be "three for the price of two" since buying one and 25 percent off would be 17.5 plus 10 for a third one is 27.5 compared to 20 for 3
<h3>Answer:</h3>
none of these has "no solution"
<h3>Explanation:</h3>
A. The solution is (8/3, 3)
B. The second equation is -1/2 times the first, so these describe the same line. The system has an <em>infinite number of solutions</em>.
C. The solution is (-4, -2)
D. The solution is (4, -2)
E. The second equation is 2 times the first, so these describe the same line. The system has an <em>infinite number of solutions</em>.
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A system of equations will have "no solution" when it describes parallel lines—lines that do not intersect. In standard form, such equations are recognizable by their different constants. For example,
- 3x -4y = -4
- 3x -4y = 20 . . . . . . 20 is different from -4
have different constants, so the equations describe parallel lines.
We could multiply one of these by -2 and the system would still be "inconsistent"—having no solution.
This answers would be 12x
The value of the given trigonometry function is 2√15/15
<h3>Half angles</h3>
Half angles are trigonometric identities used to express sine, cosine and tangent of half angles.
For instance the value of cos theta is expressed as shown below;
cosФ = cos(Ф/2+Ф/2)
cosФ = cos²Ф/2-sin²Ф/2
cosФ = cos²Ф/2-(1-cos²Ф/2)
cosФ = 1 - 2cos²Ф/2
Given the following parameters
cosФ = -7/15
Substitute
cosФ = 1 - 2cos²Ф/2
-7/15 = 1 - 2cos²Ф/2
-2cos²Ф/2 = -7/15 - 1
-2cos²Ф/2 = -8/15
cos²Ф/2 = 4/15
cosФ/2 = 2/√15
Rationalize
2/√15 * √15/√15
2√15/15
Hence the value of the given trigonometry function is 2√15/15
Learn more on trigonometry function here: brainly.com/question/2254074
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