If a and ß are zeroes of the polynomial x2 - 6x + a. Find the value of a if 3a + 2ß = 20
Answers
Following is the value of a 3alpha + 2beta = 20
Given
α,ß are the zeroes of the polynomial
=> α+ß=6-----(i)
αß=a------(ii)
Given
3α+2ß=20------(iii)
Solving (i) and (iii) we get
α=8
ß=-2
Substituting these values in (ii) we get
=> (8)(-2)=a
=> a=-16
Step-by-step explanation:
Given :-
α and ß are zeroes of the polynomial x² - 6x + a. and 3α + 2ß = 20
To find :-
Find the value of a ?
Solution :-
Given Quadratic Polynomial is x²-6x+a
Let P(x) = x²-6x+a
On Comparing this with the standard quadratic Polynomial ax²+bx+c
a = 1
b = -6
c = a
Given zeores are α and ß
We know that
The sum of the zeroes = -b/a
=>α+ß = -(-6)/1
=> α+ß = 6
=>α = 6-ß -------------(1)
The product of the zeroes = c/a
=> αß = a/1
=> αß = a --------------(2)
Given that
3α+2ß = 20
From (1)
=> 3(6-ß)+2ß = 20
=> 18 -3ß +2ß = 20
=> 18-ß = 20
=> ß = 18-20
=> ß = -2
On Substituting the value of ß in (1) then
α = 6-(-2)
=> α = 6+2 = 8
Now,
From (2)
=>a = (8)(-2)
=> a = -16
Answer:-
The value of a for the given problem is -16
Used formulae:-
→ The standard quadratic Polynomial ax²+bx+c
→ The sum of the zeroes = -b/a
→ The product of the zeroes = c/a