Answer:
v = 7
is the value for which
x = (-21 - √301)/10
is a solution to the quadratic equation
5x² + 21x + v = 0
Step-by-step explanation:
Given that
x = (-21 - √301)/10 .....................(1)
is a root of the quadratic equation
5x² + 21x + v = 0 ........................(2)
We want to find the value of v foe which the equation is true.
Consider the quadratic formula
x = [-b ± √(b² - 4av)]/2a ..................(3)
Comparing (3) with (2), notice that
b = 21
2a = 10
=> a = 10/2 = 5
and
b² - 4av = 301
=> 21² - 4(5)v = 301
-20v = 301 - 441
-20v = -140
v = -140/(-20)
v = 7
That is a = 5, b = 21, and v = 7
The equation is then
5x² + 21x + 7 = 0
Answer:
The second number would be 8 or 16
Step-by-step explanation:
Let x be the unknown number,
Since, first number = 17,
So, the difference between x and 17 = |17 - x |
According to the question,
|17 - x | = 9
17 - x = ± 9
17 - x = 9 or 17 - x = -9
17 - 9 = x or 17 + 9 = x
⇒ x = 8 or x = 26
Hence, the second number would be 8 or 26.
I’d say 485 discs are defective out of 41000
Answer: 3
Step-by-step explanation:
Distribute the 5: 15x-5=40
Add 5 from both sides: 15x=45
Divide 15 by both sides: 3
False, since it we substitute x = 4 into the equation we get y = -4 + 3 = -1