SOLUTION: Solve the simultaneous equations y = | x-5 | and y = | 3-2x | + 2.

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Question 1185746: Solve the simultaneous equations y = | x-5 | and y = | 3-2x | + 2.
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


abs%28x-5%29+=+5-x for x<5
%28x-5%29+=+x-5 for x>5

abs%283-2x%29+=+3-2x for x<3/2
abs%283-2x%29+=+2x-3 for x>3/2

So we need to look for solutions for x in three intervals: (-infinity,3/2), (3/2,5), and (5, infinity).

(1) (-infinity,3/2)

abs%28x-5%29=abs%283-2x%29%2B2
5-x=3-2x%2B2
5-x=5-2x
x=0

x=0 is in the interval we are working in, so x=0 is a solution -- or, rather, (x,y)=(0,5) is a solution.

(2) (3/2,5)

abs%28x-5%29=abs%283-2x%29%2B2
5-x=2x-3%2B2
5-x=2x-1
6=3x
x=2

x=2 is also in the interval we are working in, so (x,y)=(2,3) is a solution.

(3) (5,infinity)

abs%28x-5%29=abs%283-2x%29%2B2
x-5=2x-3%2B2
x-5=2x-1
x=-4

x=-4 is not in the interval we are working in, so this is not another solution.

ANSWER: (x,y)=(0,5) and (x,y)=(2,3)

A graph, showing the graphs of the two absolute value functions intersecting at (0,5) and (2,3)....

graph%28400%2C400%2C-2%2C8%2C-2%2C8%2Cabs%28x-5%29%2Cabs%283-2x%29%2B2%29