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The value of y varies directly with x, and y= -8 when x=2. How do you find y when x=3?

Answer 1

Kennedy Adams

When #x=3#, we have #y=-12#

As value of #y# varies directly with #x#, we have #ypropx#

i.e. #y=kxx x#, where #k# is a constant.

AS #y# takes a value #y=-8#, when #x=2#

we have #-8=kxx2# or #k=-8/2=-4#

Hence, relation is #y=-4x#

and when #x=3#, we have #y=-4xx3=-12#

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Answer 2

Eli Assouline

To find y when x=3, you can use the direct variation formula, which states that y varies directly with x. Given that y=-8 when x=2, you can set up the proportion: ( \frac{y_1}{x_1} = \frac{y_2}{x_2} ). Substituting the given values, ( \frac{-8}{2} = \frac{y}{3} ), you can solve for y: ( -8 \times \frac{3}{2} = y ), which simplifies to ( y = -12 ). Therefore, when x=3, y=-12.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.