7x³ = 28x is our equation. We want its solutions.
When you have x and different powers, set the whole thing equal to zero.
7x³ = 28x
7x³ - 28x = 0
Now notice there's a common x in both terms. Let's factor it out.
x (7x² - 28) = 0
As 7 is a factor of 7 and 28, it too can be factored out.
x (7) (x² - 4) = 0
We can further factor x² - 4. We want a pair of numbers that multiply to 4 and whose sum is zero. The pairs are 1 and 4, 2 and 2. If we add 2 and -2 we get zero.
x (7) (x - 2) (x + 2) = 0
Now we use the Zero Product Property - if some product multiplies to zero, so do its pieces.
x = 0 -----> so x = 0
7 = 0 -----> no solution
x - 2 = 0 ----> so x = 2 after adding 2 to both sides
x + 2 = 0 ---> so = x - 2 after subtracting 2 to both sides
Thus the solutions are x = 0, x = 2, x = -2.
Answer : x = 0,5,-2
Step 1 : factor left side
x(x+2)(x-5)=0
step 2 : set factors equal to 0
x=0, x+2=0 or, x-5=0
Answer:
After 3 seconds
Step-by-step explanation:
Given

Required
Seconds to attain maximum height
The maximum of a quadratic function
is calculated using:

So, we have:

Where:
and 
So:


Cancel out negatives


The length of the rectangle is 3 cm
<h3>Applications of Quadratic equations</h3>
From the question, we are to determine the value of the length of the rectangle
To find the length of the rectangle, we will determine the value of x in the given equation
The given equation is

This can be written as

Factorizing



Then,
OR 
x = 3 OR x = -8
Since, the length of the rectangle cannot be negative, the value of x is 3.
Hence, the length of the rectangle is 3 cm.
Learn more on solving quadratic equations here: brainly.com/question/8649555
We need a denominator in order to put this into a percentage. Unless the denominator is one, in which we can say 666.6666666... percent.