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sowjanyaangara
Prospective Students
 
Posts: 10
Joined: Sat Mar 02, 2013 3:38 am
 

Algebra 3ed, page 148,#16

by sowjanyaangara Wed Apr 17, 2013 12:13 pm

1) The distance between q and -1 on the number line equals to -5

quantity A=/q/(absolute value)
quantity B =3

I am unable to farm the second equation for the problem

q-(-1)=5, Q=5-1=4. But there is another solution which is -6. can anybody farm the equation for -6

Thanks
sowjanya
tommywallach
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Re: Algebra 3ed, page 148,#16

by tommywallach Tue Apr 23, 2013 1:00 am

Hey Sowjan,

There's no need to make equations here. Just be logical. The distance between q and -1 is 5. This means that q is five units away from -1.

Thus we know that q is either -6 or 4. I'm not sure why we would need an equation at all. In fact, I encourage you to get away from algebra if you're forcing it this hard. However, the algebra would simply be this:

5 = abs (q - (-1))

That's because distance is always a function of difference (subtraction). Now, we solve for the two equations. There is the straight ahead one, where we simply remove the absolute value signs:

5 = q + 1
q = 4

And the other solution, where we just multiply a side by -1 (this is how you solve for the other solution of absolute values):

-5 = q + 1
q = -6

Voila!

-t