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1 vote
Answer this and add work, show all work for math. :P

Answer this and add work, show all work for math. :P-example-1
User RahulB
by
7.7k points

2 Answers

7 votes

You know that you can spot the slope and intercept right away
IF you 'solve' the equation for 'y'. Then you'll have

y = (slope) x + (intercept) .

So for choices 'A' and 'B', you have to massage the equation
into the standard form, and then just look at it and see whether
the slope is 9/4 and the intercept is -14.

A). -9x + 4y = -56

Add 9x to each side: 4y = 9x - 56

Divide each side by 4 : y = 9/4 x - 14 <== Yes ! Good one.


B). 9x + 4y = 56

Subtract 9x from each side: 4y = -9x + 56

Divide each side by 4 : y = -9/4 + 14 <= no, signs are wrong


C). Yes. Slope is 9/4 and intercept is -14 .


D). No. Slope is 9/4 alright, but intercept is +14, not -14 .

User Iberck
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8.4k points
5 votes
Lines are in the form y=mx+b, where m is the slope and b is the y-intercept.  This line is thus y=9/4x-14, so C is correct.  Multiplying by four, we get 4y=9x-56.  Adding 56 and subtracting 4y, we see that 9x-4y=56, and multiplying by -1, we get 4y-9x=-56, so A is also correct.  At this point, it is clear that B and D are incorrect, so A and C only are correct.
User Matthew Pateman
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8.6k points