Question

the equation x^2+bx+c=0 has roots -5 and 7. find the value of b and the value of c.

Answer 1

$x^2+bx+c=(x+5)(x-7).$

$x^2+bx+c=x^2+(5-7)x-5*7.$

$x^2+bx+c=x^2-2x-35.$

$b=-2, \;c=-35.$