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 132 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
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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