Question

I recently took a test in my Algebra 1 class. This was on the test (that I most likely failed)and it said something about vertical motion. The problem is below. Try to solve it, please! Thanks!
2=-t^2+4+5

Answer 1

OK.                                         2 = -t² + 4t + 5

Subtract 2 from each side:     0 = -t² + 4t + 3

Multiply the right side by  -1 :  0 = t² - 4t - 3

Unfortunately, this can't be factored.  The only other way I know
to find the solutions to a quadratic equation is with the use of the
quadratic formula.  When you do that, you get these solutions:

     t = 2 + √7 = about  4.65
and
     t = 2 - √7 = about  -0.65 .

If this equation comes from a problem that involves real people throwing
real things into the air and making vertical motion, then you want only the
positive solution.