document.write( "Question 81640: The sum of two numbers is 112. The second is 7 more than 4 times the first. What are the two numbers? \n" ); document.write( "

Algebra.Com's Answer #58496 by tutorcecilia(2152) $\"\"$ $\"About$

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Sum=to add
\n" ); document.write( "is= equals (=)
\n" ); document.write( "two numbers = x + y
\n" ); document.write( "7 more = add 7
\n" ); document.write( "4 times = multiply the first number by 4
\n" ); document.write( "Total = 112
\n" ); document.write( "..
\n" ); document.write( "So, x+y=112
\n" ); document.write( "The first number = x
\n" ); document.write( "The second number = y = 4x+7
\n" ); document.write( ".
\n" ); document.write( "x+y=112
\n" ); document.write( "x+(4x+7)=112
\n" ); document.write( "x+4x+7=112 [combine like-terms and solve for the x-term]
\n" ); document.write( "5x+7=112
\n" ); document.write( "5x+7-7=112-7
\n" ); document.write( "5x=105
\n" ); document.write( "5x/5=105/5
\n" ); document.write( "x=21
\n" ); document.write( ".
\n" ); document.write( "To find the second number (y), plug (x=21) back into the original formula and solvefor the y-term:
\n" ); document.write( "x+y=112
\n" ); document.write( "21+y=112
\n" ); document.write( "21-21+y=112-21
\n" ); document.write( "y=91
\n" ); document.write( ".
\n" ); document.write( "checking:
\n" ); document.write( "x+y=112
\n" ); document.write( "21+91-112
\n" ); document.write( "112=112 [checks out}
\n" ); document.write( " \n" ); document.write( "

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