Question

if 3 is a zero of p(x)= 3x²+x-2a then the value of a is​

Answer 1

Answer:

Ans is = 9

Step-by-step explanation:

It is given that 3 is a zero of the polynomial p(x)=3x

3

−x

2

−ax−45 which means that p(3)=0, so let us substitute x=3 in p(x) to find the value of a as shown below:

p(3)=3(3)

3

−(3)

2

−a(3)−45

⇒0=(3×27)−9−3a−45

⇒0=81−9−3a−45

⇒0=81−54−3a

⇒0=27−3a

⇒3a=27

⇒a=

3

27

⇒a=9

hence, a=9.

Answer 2

p(x) = 3x² + x - 2a

put x = 3

3(3)² + (3) - 2a = 0

27 + 3 - 2a = 0

30 - 2a = 0

30 = 2a

30/2 = a

15 = a

Value of a is 15.