algebra word problem

[afrazer721]

If a jogger runs at a speed of x miles per hour and burns 6x^2+20x+25 calories per hour, how fast should the jogger run to burn 505 calories in one hour?

Put equation into standard form: 6x^2+20x-480=0

Use quadratic formula to get root(s) of equation to plug into x to get how fast jogger runs to burn 505 calories in an hour.

 

[Deleted member 4993]

If a jogger runs at a speed of x miles per hour and burns 6x**2+20x+25 calories per hour, how fast should the jogger run to burn 505 calories in one hour? Work out steps to answer, please.

see:

http://www.freemathhelp.com/forum/threads/74063-algebra-word-problem