One of the roots of the quadratic equation x2 -10x + K=0 is
8, then the value of Kis -
(a) ৪
(b) -8 (c) -16
(d) 16
Answers
Answer:
et us first discuss the maximum:
The largest four digit number is 9999, and thus, a maximum value can be obtained by adding 9999 and 9999, and the resultant number will be having the maximum number of digits.
9999+9999=19998
Therefore, the maximum number of digits of the resultant number, when two four-digit numbers are added is 5.
Let us now discuss the minimum:
The smallest four digit number is 1000, and thus, a minimum value can be obtained by adding 1000 and 1000, and the resultant number will be having the minimum number of digits.
1000+1000=2000
Therefore, the minimum number of digits of the resultant number, when two four-digit numbers are added is 4.
Hope this helps.
Given :
It is given that one of the roots of the quadratic equation x²-10x+k=0 is 8.
To find :
We've to find the value of k in the quadratic equation.
Solution :
Now, we'll substitute x=8 in the equation and find the value of k :
→ x²-10x+k=0
→ (8)²-10(8)+k=0
→ 64-80+k=0
→ -16+k=0
→ k=16
Verification :
Here, we'll substitute x=8 as well as k=16 in the quadratic equation and verify :
→ x²-10x+k=0
→ (8)²-10(8)+16=0
→ 64-80+16=0
→ -16+16=0
→ 0=0
→ LHS = RHS
→ Hence, verified!
Therefore, Option (D) 16 is right answer.