document.write( "Question 827531: A soccer ball is kicked from the ground, and its height in meters above ground is modeled by the function h(t)=-4.9t^2+19.6t, where t represents the time in seconds after the ball is kicked. How long is the ball higher then 10 meters. \n" ); document.write( "
Algebra.Com's Answer #498742 by TimothyLamb(4379)\"\" \"About 
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\n" ); document.write( "h(t) = -4.9t^2 + 19.6t
\n" ); document.write( "h(t) = -4.9t^2 + 19.6t = 10
\n" ); document.write( "h(t) = -4.9t^2 + 19.6t - 10 = 0
\n" ); document.write( "---
\n" ); document.write( "the above quadratic equation is in standard form, with a=-4.9, b=19.6, and c=-10
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\n" ); document.write( "to solve the quadratic equation, by using the quadratic formula, copy and paste this:
\n" ); document.write( "-4.9 19.6 -10
\n" ); document.write( "into this solver: https://sooeet.com/math/quadratic-equation-solver.php
\n" ); document.write( "---
\n" ); document.write( "the quadratic has two real roots at:
\n" ); document.write( "---
\n" ); document.write( "t = 0.600291576
\n" ); document.write( "t = 3.39970842
\n" ); document.write( "dt = 3.39970842 - 0.600291576
\n" ); document.write( "dt = 2.799416844000000
\n" ); document.write( "---
\n" ); document.write( "answer:
\n" ); document.write( "the ball is above 10 meters height for 2.8 seconds
\n" ); document.write( "---
\n" ); document.write( "Solve and graph linear equations:
\n" ); document.write( "https://sooeet.com/math/linear-equation-solver.php
\n" ); document.write( "---
\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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