document.write( "Question 262223: I'm not sure what type of equation this is, but I need help on how the answer was found. I am taking an SAT soon, and this is an example in my test booklet. I don't know how they found the answers for these equations, can you please help me find out how to find the answer on my own?\r
\n" ); document.write( "\n" ); document.write( "Question:
\n" ); document.write( "What value of X satisfies both of the equations below?
\n" ); document.write( "|4x-7|=5 and |3-8x|=1\r
\n" ); document.write( "\n" ); document.write( "Since |4x-7|=5, the value of 4x-7 is either 5 or -5.
\n" ); document.write( "4x-7=5 4x-7=-5
\n" ); document.write( "4x=12 Or 4x=2
\n" ); document.write( "x=3 x=1/2 \r
\n" ); document.write( "\n" ); document.write( "(I don't see how 4x=12, x=3, 4x=2, etc...)\r
\n" ); document.write( "\n" ); document.write( "Since |3-8x|=1, the value of 3-8x is either 1 or -1.
\n" ); document.write( "3-8x=1 3-8x=-1
\n" ); document.write( "8x=2 Or 8x=4
\n" ); document.write( "x=1/4 x=1/2 \r
\n" ); document.write( "\n" ); document.write( "(again, I don't know how they got the answers for
\n" ); document.write( " the equations.)\r
\n" ); document.write( "\n" ); document.write( "The two values of x that satisfy the second equation are 1/4 and 1/2. You are asked to find the value of x that satisfies BOTH equations. That value is 1/2. The answer can be entered in the grid as 1/2 or .5.\r
\n" ); document.write( "\n" ); document.write( "I would appreciate some help on how they found the answers for the equations because I have no idea how this was answered.
\n" ); document.write( "
\n" ); document.write( "

Algebra.Com's Answer #193170 by drk(1908)\"\" \"About 
You can put this solution on YOUR website!
What value of X satisfies both of the equations below?
\n" ); document.write( "(i) \"abs%284x-7%29=5\"
\n" ); document.write( "(ii) \"abs%283-8x%29=1\"
\n" ); document.write( "here are my steps:
\n" ); document.write( "set (i) = 5 and then -5. solve for x.
\n" ); document.write( "\"%284x-7%29+=+5\"
\n" ); document.write( "add 7 to both sides to get
\n" ); document.write( " \"4x+=+12\"
\n" ); document.write( "divide by 4 on both sides to get
\n" ); document.write( "\"x+=+3\"
\n" ); document.write( "---
\n" ); document.write( "\"4x-7+=+-5\"
\n" ); document.write( "add 7 to both sides to get
\n" ); document.write( "\"4x+=+2\"
\n" ); document.write( "divide by 4 to get
\n" ); document.write( " \"x+=+1%2F2\"
\n" ); document.write( "---
\n" ); document.write( "Now we look at (ii).
\n" ); document.write( "setting it = 1 or -1, solving for x, we get
\n" ); document.write( "\"3-8x+=+1\"
\n" ); document.write( "subtract 3 from both sides to get
\n" ); document.write( "\"-8x+=+-2\"
\n" ); document.write( "divide by -8 to get
\n" ); document.write( "\"x+=+1%2F4\"
\n" ); document.write( "--
\n" ); document.write( "\"3-8x+=+-1\"
\n" ); document.write( "subtract 3 from both sides to get
\n" ); document.write( "\"-8x+=+-4\"
\n" ); document.write( "divide by -8 to get
\n" ); document.write( "\"x+=+1%2F2\"
\n" ); document.write( "--
\n" ); document.write( "Now looking at our answers we see that x = 1/2 is the same. So it is the answer we need.
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