The equation above has three unique roots at , , and . If , , and are constants, what is the value of ?A)B)C)D) Loading... Page navigation ← Daily PWN 148 Daily PWN 134 →

We know the y intercept is at -90 because if x is set to zero we get =-90 x^3 + bx^2+ cx+90 =0 is the same as x^3+Bx^2+cx= -90 we know roots at -5 and 3 so therefore ( X+5) because (-5 +5) gives us the one root of 0 and (X-3)because (3-3) gives us another zero so we have ( x+5)(x-3) ( x+k) =-90 setting xs to zero we end up with 5*-3*k =-90 -15(k ) =-90 k= -90/-15 k= 6 Log in to Reply

## Comments (1)

We know the y intercept is at -90

because if x is set to zero we get =-90

x^3 + bx^2+ cx+90 =0

is the same as x^3+Bx^2+cx= -90

we know roots at -5 and 3 so therefore

( X+5) because (-5 +5) gives us the one root of 0 and

(X-3)because (3-3) gives us another zero

so we have ( x+5)(x-3) ( x+k) =-90

setting xs to zero we end up with

5*-3*k =-90

-15(k ) =-90

k= -90/-15

k= 6