It will cost 4.98.
Explanation: If you divide 7.47 by 3, you get 2.49. One yard plus one yard equals two yards. Multiply 2.49 by 2 to get the answer.
Answer:
Step-by-step explanation:
4x - 6y = 8 ⇔ - 6y = -4x + 8 ⇔ y = 4/6x - 8/6 ⇔ y = 2/3x - 4/3
The question is somewhat poorly posed because the equation doesn't involve <em>θ</em> at all. I assume the author meant to use <em>x</em>.
sec(<em>x</em>) = csc(<em>x</em>)
By definition of secant and cosecant,
1/cos(<em>x</em>) = 1/sin(<em>x</em>)
Multiply both sides by sin(<em>x</em>) :
sin(<em>x</em>)/cos(<em>x</em>) = sin(<em>x</em>)/sin(<em>x</em>)
As long as sin(<em>x</em>) ≠ 0, this reduces to
sin(<em>x</em>)/cos(<em>x</em>) = 1
By definition of tangent,
tan(<em>x</em>) = 1
Solve for <em>x</em> :
<em>x</em> = arctan(1) + <em>nπ</em>
<em>x</em> = <em>π</em>/4 + <em>nπ</em>
(where <em>n</em> is any integer)
In the interval 0 ≤ <em>x</em> ≤ 2<em>π</em>, you get 2 solutions when <em>n</em> = 0 and <em>n</em> = 1 of
<em>x</em> = <em>π</em>/4 <u>or</u> <em>x</em> = 5<em>π</em>/4
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Define x :
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Let Cheryl be x years old.
Cheryl = x
Lisa = x + 6
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In two years time:
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Cheryl = x + 2
Lisa = x + 8
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Lisa will be twice as old as Cheryl :
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x + 8 = 2(x + 2)
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Solve x :
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x + 8 = 2(x + 2)
x + 8 = 2x + 4
x = 4
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Find their age :
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Cheryl = x = 4
Lisa = x + 6 = 4 + 6 = 10
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Answer: Lisa is 10 years old now.
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The correct answer is option D
The solution is shown below:
