document.write( "Question 669293: Help explain answer to question B cannot understand where the 25 = (x + 8) + 3x + 5) came from to solve this question\r
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\n" ); document.write( "\n" ); document.write( "Given that S is a point on RT, use the given lengths to calculate the following:
\n" ); document.write( "a. If RT = 21 and ST = 8, calculate RS.
\n" ); document.write( "b. If RS = 17 and ST = 34, calculate RT.
\n" ); document.write( "c. If RT = 25, RS = x + 8, and ST = 3x + 5, calculate ST.
\n" ); document.write( "d. If S is the midpoint of RT, RS = 5x − 4 and ST = 3x + 6, calculate RT. \r
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\n" ); document.write( "\n" ); document.write( "Solution
\n" ); document.write( " A.Since RT = RS + ST, we have 21 = RS + 8, so RS = 21 − 8 = 13.\r
\n" ); document.write( "\n" ); document.write( "B
\n" ); document.write( "Since RT = RS + ST, we have RT = 17 + 34 = 51.
\n" ); document.write( "Since RT = RS + ST, we have
\n" ); document.write( "25 = (x + 8) + 3x + 5)
\n" ); document.write( "25 = 4x + 13
\n" ); document.write( "12 = 4x
\n" ); document.write( "x = 3
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Algebra.Com's Answer #416269 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "\"RT+=+25\"........given\r
\n" ); document.write( "\n" ); document.write( "\"RS+=+x+%2B+8\", and \"ST+=+3x+%2B+5\".........given\r
\n" ); document.write( "\n" ); document.write( "given also that \"S\" is a point \"on\"\"+RT\" which means \"RT=RS+%2BST\"\r
\n" ); document.write( "\n" ); document.write( "now substitute given values for \"RT+=+25\",\"RS+=+x+%2B+8\", and \"ST+=+3x+%2B+%0D%0A%0D%0A5\" in \"RT=RS+%2BST\" and you have \"25=%28x+%2B+8%29+%2B%283x+%2B+5%29\"
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