.y is inversely proportional to (x + 3) ?. When x = 2, y = 8. Find y when x = 7. A 100 B. 4 C. 2. D. 16<

Question

.y is inversely proportional to (x + 3) ?.
When x = 2, y = 8.
Find y when x = 7.
A 100
B. 4
C. 2.
D. 16
OA

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Huyền Thanh 3 years 2021-08-24T12:34:09+00:00 2 Answers 6 views 0

Answers ( )

  1. Cherry
    0
    2021-08-24T12:35:09+00:00
    Reply

    Answer:

    B

    Step-by-step explanation:

    y = k/(x + 3)

    Let x = 2

    Let y = 8

    k = ?

    8 = k/(2 + 3)      Combine the terms on the right

    8 = k/(5)            Multiply both sides by 5

    8*5 = k

    k = 40

    Let x = 7

    y = 40/(7 + 3)

    y = 40/10

    y = 4

  2. lethu
    0
    2021-08-24T12:35:48+00:00
    Reply

    y∝ \frac{1}{x + 3}

    y1∝ \frac{1}{x1 + 3} \\ 8 ∝ \frac{1}{2 + 3} ......(1)

    y2∝ \frac{1}{x2 + 3} .......(2)

    DIVIDE BOTH THE EQUATION

    \frac{8}{y2} = \frac{ 7- + 3}{ 5} \\ \frac{ 5\times 8}{10} = y2 \\ 4= y2

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