If (x-6) is the factor of P(x) = x^{2} - (4a-1)x + 2b and Q(x) = x^{2} - (2a-5)x + 6b then what is b-a?
Help please.
Answers
Answer:
-10
Step-by-step explanation:
(i)
Given, P(x) = x² - (4a - 1)x + 2b
Since, (x - 6) is the factor of p(x), then p(6) = 0
P(6) = (6)² - (4a - 1)6 + 2b
⇒ 0 = 36 - 24a + 6 + 2b
⇒ 0 = 42 - 24a + 2b
⇒ -24a + 2b = -42
(ii)
Given, Q(x) = x² - (2a - 5)x + 6b
Since, (x - 6) is a factor of f(x), So f(6) = 0
f(6) = (6)² - (2a - 5)6 + 6b
⇒ 0 = 36 - 12a + 30 + 6b
⇒ 0 = 66 - 12a + 6b
⇒ -12a + 6b = -66
On solving (i) & (ii) * 2, we get
⇒ -24a + 2b = -42
⇒ -24a + 12b = -132
--------------------------
-10b = 90
b = -9
Substitute b = -9 in (i), we get
⇒ -24a + 2b = -42
⇒ -24a + 2(-9) = -42
⇒ a = 1
Now,
b - a = -9 - 1
= -10
Hope it helps!
Since (x-6) is a factor of the equations,
Value of x=6
Put the value of x in both the equations
Then you will get 1--------24
a-2b=42
2-----12a-6b=66
Solve the equations
Get the value of a and b