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quester [9]
3 years ago
15

30 POINTSSSSSS If y varies directly as x, and y = 42 as x = 6, find y for the x-value 3

Mathematics
2 answers:
Yanka [14]3 years ago
7 0

Answer:

  • y = 7x
  • y = 21

Step-by-step explanation:

<u>Direct variation formula:</u>

  • y = kx

<u>Given:</u>

  • x = 6, y = 42

<u>Find k:</u>

  • 42 = 6k
  • k = 42/6
  • k = 7

<u>The equation of line is:</u>

  • y = 7x

<u>Now, when x = 3, the value of y is:</u>

  • y = 7*3 = 21
Alex787 [66]3 years ago
3 0

\\ \sf\longmapsto x\propto y

\\ \sf\longmapsto x_1y_2=x_2y_1

\\ \sf\longmapsto 6y_2=42(3)

\\ \sf\longmapsto 6y_2=126

\\ \sf\longmapsto y_2=\dfrac{126}{6}

\\ \sf\longmapsto y_2=21

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<h3>What is the decision rule for the p-value approach to hypothesis testing?</h3>

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