Problem page write the quadratic equation whose roots are 5 and −4 , and whose leading coefficient is 1 .

The first thing to do in this case is to write the polynomial in a factored form for the roots.
 We have then:
 (x-5) * (x + 4) = 0
 Then, rewriting the quadratic equation:
 (x-5) * (x + 4)
 x ^ 2 + 4x -5x -20
 x ^ 2 -x -20
 
 the quadratic equation whose roots are 5 and -4, and whose leading coefficient is 1 is
 x ^ 2 -x -20