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September 23, 2014

September 23, 2014

Posted by **Beth** on Tuesday, January 25, 2011 at 6:44am.

If y = 10 when x = −5, what is the value of y when x = 30?

- maths -
**Reiny**, Tuesday, January 25, 2011 at 8:43am"y is directly proportional to x" --- y = kx , where k is a constant

for the given:

10 = -5k

k = -2

so y = -2x is your equation:

so when x = 20 , y = ......

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