Question

What should be subtracted from the polynomial z²-20z+30, so that (z-15) is a factor of the resulting polynomial?

Answer 1

Answer:

Substract (-45) .

Step-by-step explanation:

Devide (z²-20z+30) by (z-15).

(z²-20z+30)/(z-15)

The quotient will be (z-5) and the reminder will be

(-45).

As we know, Dividend=(Divisor×quotient)+reminder

Then, We need to substract the reminder which is (-45) from divident which is (z²-20z+30).

Lets verify, (z²-20z+30)-(-45)=(z²-20z+75)

Now, if we factorise it, we will get (z-15) and z-5).