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3 years ago

If x and y vary directly, and x = 10 when y = 3, what will be the value of x when y = 9?

Mathematics

2 answers:

mafiozo [28]3 years ago

8 0

Y=3 x=10
X3 X3
y=9 x=30

saw5 [17]3 years ago

3 0

Answer: The required value of x is 30.

Step-by-step explanation: Given that the variables x and y varies directly. And, x = 10 when y = 3.

We are to find the value of x when y = 9.

Given that x and y varies directly. So, we have

$y\propto x\\\\\Rightarrow y=px,~~~~~~~~~~~\textup{[where p is the proportionality constant]}.$

When x = 10, y = 3, then

$3=p\times10\\\\\Rightarrow p=\dfrac{3}{10}.$

So, the relation between x and y will be

$y=\dfrac{3}{10}x\\\\\Rightarrow x=\dfrac{10}{3}y.$

Therefore, when y = 9, then

$x=\dfrac{10}{3}\times9=30.$

Thus, the required value of x is 30.

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b. The equation of the diagonal line AC is y = 5 - x

The equation of the diagonal line BD is y = 5 - x

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a. The length, l, of the sides of the given quadrilateral are given as follows;

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c. Comparing the lines AC and BD with equations, y = 5 - x and y = x, which are straight line equations of the form y = m·x + c, where m = the slope and c = the x intercept, we have;

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