document.write( "Question 820657: Lauren shot a rocket from her backyard.The equation that models this scenario is y=-16x^2+80x+10. For how long was Laurens rocket above 74 feet? \n" ); document.write( "
Algebra.Com's Answer #493650 by TimothyLamb(4379)\"\" \"About 
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\n" ); document.write( "y = -16x^2 + 80x + 10 = 74
\n" ); document.write( "-16x^2 + 80x + 10 = 74
\n" ); document.write( "-16x^2 + 80x - 64 = 0
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\n" ); document.write( "the above quadratic equation is in standard form, with a=-16, b=80, and c=-64
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\n" ); document.write( "to solve the quadratic equation, by using the quadratic formula, copy and paste this:
\n" ); document.write( "-16 80 -64
\n" ); document.write( "into this solver: https://sooeet.com/math/quadratic-equation-solver.php
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\n" ); document.write( "the two real roots (i.e. the two x-intercepts), of the quadratic are:
\n" ); document.write( "x = 1
\n" ); document.write( "x = 4
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\n" ); document.write( "answer:
\n" ); document.write( "the rocket was above 74 feet altitude between 1 second and 4 seconds after launch
\n" ); document.write( "so for a total of 3 seconds
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\n" ); document.write( "Solve and graph linear equations:
\n" ); document.write( "https://sooeet.com/math/linear-equation-solver.php
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\n" ); document.write( "Solve quadratic equations, quadratic formula:
\n" ); document.write( "https://sooeet.com/math/quadratic-formula-solver.php
\n" ); document.write( "---
\n" ); document.write( "Solve systems of linear equations up to 6-equations 6-variables:
\n" ); document.write( "https://sooeet.com/math/system-of-linear-equations-solver.php \n" ); document.write( "
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