If Y varies directly as X and Y= 79 when X= 49, Find Y if X = 9

Mathematics

1 answer:

ryzh [129]3 years ago

7 0

Answer:

y = 14.5

Step-by-step explanation:

given that y varies directly as x

mathematically,

y ∝ x

y = kx .............................................. where k is the constant of proportionality.

k = y /x

given that

y = 79

x = 49

k = 79/49

k = 1.61

to find y when x = 9

from

y = kx

y = 1.61 × 9

y = 14.5

therefore the value of y when x = 9 in ths variation is evaluated to be equals to 14.5

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