document.write( "Question 114226This question is from textbook
\n" ); document.write( ": Four hamburgers and three orders of french fries cost $5.15. Three hamburgers and five orders of fries cost $5.10. What would one hamburger and one order of fries cost? \n" ); document.write( "

Algebra.Com's Answer #83171 by Fombitz(32388) $\"\"$ $\"About$

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Let's let H=cost of hamburger and F=cost of fries.
\n" ); document.write( "1. $\"4H%2B3F=5.15\"$
\n" ); document.write( "2. $\"3H%2B5F=5.10\"$
\n" ); document.write( "Let me use equation 1 to solve for H in terms of F and then substitute into equation 2.
\n" ); document.write( "1. $\"4H%2B3F=5.15\"$
\n" ); document.write( " $\"4H=5.15-3F\"$
\n" ); document.write( " $\"H=1.2875-0.75F\"$
\n" ); document.write( "Now substitute into 2.
\n" ); document.write( "2. $\"3H%2B5F=5.10\"$
\n" ); document.write( " $\"3%281.2875-0.75F%29%2B5F=5.10\"$
\n" ); document.write( " $\"3%281.2875%29-3%280.75F%29%2B5F=5.10\"$
\n" ); document.write( " $\"3.8625-2.25F%2B5F=5.10\"$
\n" ); document.write( " $\"3.8625%2B2.75F=5.10\"$
\n" ); document.write( " $\"2.75F=1.2375\"$
\n" ); document.write( " $\"F=0.45\"$
\n" ); document.write( "Now that you have F, you can substitute into either equation to find H.
\n" ); document.write( "2. $\"3H%2B5F=5.10\"$
\n" ); document.write( " $\"3H%2B5%280.45%29=5.10\"$
\n" ); document.write( " $\"3H%2B2.25=5.10\"$
\n" ); document.write( " $\"3H=2.85\"$
\n" ); document.write( " $\"H=0.95\"$
\n" ); document.write( "Hamburgers cost $0.95 and french fries cost $0.45.
\n" ); document.write( "One hamburger and one order of fries would cost $1.40. \n" ); document.write( "

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