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How do you solve for x in #y = (1+4x)/(7-9x)#?

Answer 1

Kennedy Adams

#x=(7y-1)/(9y+4), if, y!=-4/9#.

Given that, #y=(1+4x)/(7-9x)#

#rArr y(7-9x)=1+4x, i.e., 7y-9xy=1+4x#.

# rArr 7y-1=9xy+4x=x(9y+4)#.

# rArr (7y-1)/(9y+4)=x, if, y!=-4/9#.

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Answer 2

Hazel Anglin

To solve for $x$ in the equation $y = \frac{{1+4x}}{{7-9x}}$ , we can follow these steps:

Cross multiply to eliminate the denominator: $y(7-9x) = 1 + 4x$ .
Expand and simplify the equation: $7y - 9xy = 1 + 4x$ .
Rearrange terms to isolate the variable $x$ : $9xy + 4x = 7y - 1$ .
Factor out $x$ from the terms: $x(9y + 4) = 7y - 1$ .
Divide both sides by $9y + 4$ to solve for $x$ : $x = \frac{{7y - 1}}{{9y + 4}}$ .

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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.