document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=821708>Question 821708</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Redwood Growth\r<BR>\n" );
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document.write( "The growth, f(x), in inches per year of a redwood tree less than 30 years old is given by the function f(x)= -0.02x^2+x+1, where x represents the number of inches of rainfall per year.\r<BR>\n" );
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document.write( "a)Find the growth per year of a redwood tree in a year in which there is 12 inches of rainfall.\r<BR>\n" );
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document.write( "b) If the growth of a redwood tree in one year is 10 inches, find the number of inches of rainfall for that year. Round answer to 2 decimal places. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #494342 by </B><A HREF=/tutors/aboutme.mpl?userid=TimothyLamb><B>TimothyLamb(4379)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=TimothyLamb><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=TimothyLamb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=494342\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> ---<BR>\n" );
document.write( "f(x) = -0.02x^2 + x + 1<BR>\n" );
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document.write( "answer a:<BR>\n" );
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document.write( "when rainfall is 12 inches per year (x = 12):<BR>\n" );
document.write( "f(12) = -0.02(12)^2 + 12 + 1<BR>\n" );
document.write( "f(12) = 10.12 inches growth per year when x=12 inches of rainfall that year<BR>\n" );
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document.write( "answer b:<BR>\n" );
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document.write( "when tree growth is 10 inches per year (f(x) = 10):<BR>\n" );
document.write( "f(x) = 10 = -0.02x^2 + x + 1<BR>\n" );
document.write( "-0.02x^2 + x - 9 = 0<BR>\n" );
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document.write( "the above quadratic equation is in standard form, with a=-0.02, b=1, and c=-9<BR>\n" );
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document.write( "to solve the quadratic equation, by using the quadratic formula, copy and paste this:<BR>\n" );
document.write( "-0.02 1 -9<BR>\n" );
document.write( "into this solver: https://sooeet.com/math/quadratic-equation-solver.php<BR>\n" );
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document.write( "the two real roots (i.e. the two x-intercepts), of the quadratic are:<BR>\n" );
document.write( "x = 11.7712434<BR>\n" );
document.write( "x = 38.2287566<BR>\n" );
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document.write( "10 inches of growth per year occurs under two distinct conditions:<BR>\n" );
document.write( "condition 1: rainfall = 11.8 inches for that year<BR>\n" );
document.write( "condition 2: rainfall = 38.2 inches for that year<BR>\n" );
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document.write( "Solve and graph linear equations:<BR>\n" );
document.write( "https://sooeet.com/math/linear-equation-solver.php<BR>\n" );
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document.write( "Solve quadratic equations, quadratic formula:<BR>\n" );
document.write( "https://sooeet.com/math/quadratic-formula-solver.php<BR>\n" );
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document.write( "Solve systems of linear equations up to 6-equations 6-variables:<BR>\n" );
document.write( "https://sooeet.com/math/system-of-linear-equations-solver.php </SPAN>\n" );
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