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If y varies directly with x and y = -11.7 when x = -3, find the value of y when x = 7.

2 Answers

1 vote

Answer: 27.3

Explanation:

Joint Variation

User Rashaan
by
7.6k points
5 votes

Answer:

y = 27.3

Explanation:

To find the value of y when x = 7 we must first find the relationship between them.

The statement

y varies directly with x is written as

y = kx

where k is the constant of proportionality

From the question

when y = - 11.7

x = - 3

We have

- 11.7 = -3k

Divide both sides by - 3

k = 3.9

So the formula for the variation is

y = 3.9k

When x = 7

y = 3.9(7)

y = 27.3

Hope this helps you

User Suchita Mukherjee
by
8.1k points