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: 7.8 ⋅ 
Step-by-step explanation:
To write a linear expression in standard form, rearrange the terms in alphabetical order.
7.8 ⋅ 
The factors is 5,4,3,6,12
D. Use the formula V=πr^2 h.
Answer:
1) x-3=0
4) 6=2x
6) x²=9
Step-by-step explanation:
x-3=0
x=3
----
1+x = 2
x = 2-1
x = 1
----
9-x=3
9-3=x
6=x
----
6=2x
6/2=x
3=x
----
x/5=3
x=3*5
x=15
----
x²=9
x=±3
These are the value of x solved for each equations. If you have any questions, feel free to ask.