SOLUTION: On a number line, point B is at a distance of 5 from point C, and point D is at a distance of 7 from point C. What is the distance from point B to point D? Please help

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Question 1040804: On a number line, point B is at a distance of 5 from point C, and point D is at a distance of 7 from point C. What is the distance from point B to point D? Please help
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39616) About Me  (Show Source):
You can put this solution on YOUR website!
You could literally draw the number line and the description and find the answer.

This system is also a transcription for the description:
system%28abs%28b-c%29=5%2Cabs%28d-c%29=7%29
The question asks, what is abs%28b-d%29 or abs%28d-b%29 ?

Answer by ikleyn(52775) About Me  (Show Source):
You can put this solution on YOUR website!
.
On a number line, point B is at a distance of 5 from point C, and point D is at a distance of 7 from point C.
What is the distance from point B to point D? Please help
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Case 1. The points B and D are on one side from C (let say, both B and D are to the left from C). 
Then |B-D| = |7-5| = 2.  The distance between B and D is 2 units.

Case 2. The points B and D are on one side from C (let say, both B and D are to the right from C). 
Then |B-D| = |7-5| = 2.  The distance between B and D is 2 units.  Same as Case 1.

Case 3. The points B and D are on different sides from C (let say, B is on the left side, while D is on the right side from C). 
Then |B-D| = |7+5| = 12.  The distance between B and D is 12 units.

Case 4. The points B and D are on different sides from C (let say, B is on the right side, while D is on the left side from C). 
Then the distance |B-D| = |7+5| = 12.  The distance between B and D is 12 units.  Same as Case 3.

5. There are no other cases.

Answer.  There are two solutions and exactly two possibilities: |B-D| = 2 or 12.