document.write( "Question 89956: the demand and supply equations for a certain item are given by
\n" ); document.write( "d=-5p+40
\n" ); document.write( "S=-p^2+30p-8\r
\n" ); document.write( "\n" ); document.write( "Find the equillibrium price\r
\n" ); document.write( "\n" ); document.write( "A)1.43
\n" ); document.write( "B)1.57
\n" ); document.write( "C)1.71
\n" ); document.write( "D)1.29
\n" ); document.write( "

Algebra.Com's Answer #65354 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
The demand and supply equations for a certain item are given by
\n" ); document.write( "d = -5p + 40
\n" ); document.write( "S = -p^2 + 30p - 8
\n" ); document.write( "Find the equilibrium price:
\n" ); document.write( ":
\n" ); document.write( "Equilibrium price occurs when demand = Supply:
\n" ); document.write( "d = s
\n" ); document.write( ":
\n" ); document.write( "-5p + 40 = -p^2 + 30p - 8
\n" ); document.write( ":
\n" ); document.write( "Arrange as a quadratic equation on the left:
\n" ); document.write( "+p^2 - 5p - 30p + 40 + 8 = 0
\n" ); document.write( ":
\n" ); document.write( "p^2 - 35p + 48 = 0
\n" ); document.write( ":
\n" ); document.write( "Use the quadratic formula to find p: a=1; b=-35; c=48
\n" ); document.write( "\"p+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( ":
\n" ); document.write( "\"p+=+%28-%28-35%29+%2B-+sqrt%28+-35%5E2+-+4+%2A+1+%2A+48+%29%29%2F%282%2A1%29+\"
\n" ); document.write( ":
\n" ); document.write( "\"p+=+%28%2B35+%2B-+sqrt%281225+-+192+%29%29%2F%282%29+\"
\n" ); document.write( ":
\n" ); document.write( "\"p+=+%28%2B35+%2B-+sqrt%281033%29%29%2F%282%29+\"
\n" ); document.write( ":
\n" ); document.write( "I'll let you do the math and find the value of p:
\n" ); document.write( "
\n" ); document.write( "
\n" );