document.write( "Question 818153: Please help. I have a hard time with word problems. Here is the question.
\n" ); document.write( "\"An international calling plan charges a rate per minute plus a flat fee. A 10 minute call to France cost $3.19. A 15 minute call to France costs $4.29. Write and solve a linear equation to find the cost of a 12 minute call to France.\r
\n" ); document.write( "\n" ); document.write( "Please help me.
\n" ); document.write( "Thanks \n" ); document.write( "

Algebra.Com's Answer #492379 by richwmiller(17219) $\"\"$ $\"About$

You can put this solution on YOUR website!
we are looking for a linear equation in the form y=mx+b
\n" ); document.write( "the flat fee will B
\n" ); document.write( "the x will be the number of minutes
\n" ); document.write( "here we have two sets of x and y
\n" ); document.write( "(10, 319),
\n" ); document.write( "(15, 429)
\n" ); document.write( "find m the slope
\n" ); document.write( "429-319/15-10
\n" ); document.write( "110/5
\n" ); document.write( "22
\n" ); document.write( "y-319=22*(x-10)
\n" ); document.write( "y-319=22x-220\r
\n" ); document.write( "\n" ); document.write( "y = 22x+99\r
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\n" ); document.write( "\n" ); document.write( "substitute 12 in for x to find y the cost of the phone call
\n" ); document.write( "y=264+99
\n" ); document.write( "y=$3.63\r
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