Answer: 8 hours
Step-by-step explanation:
Let x be the time taken by each person to paint the fence.
Given: Tom and Becky can paint Jim's fence together in 12 hours.
Since all people paint at the same rate, then we have the following equation ;-

Thus, the time taken by each person to paint the fence alone = 24 hours
Now, the time taken by all three paint together:-

Hence, it would take 8 hours if all three paint together.
The relationship between wavelength and frequency is expressed by the equation λν=c where λ is the wavelength, v is the frequency and c is the speed of light which has a value of 3x10^8 m/s.
λν=c
λ(3 × 10^9)= 3x10^8
λ = 0.1 m
Hope this answers the question.
Area=length*height
Area=(25)*(8)
Area=200 feet^2
to find the area of a rectangle is LxW=A
plug in the given numbers you have
L = 7
W = x-8
A = 42
7 * x-8 = 42
7x-56= 42
solve for X
Answer:
y = x² - 4x - 21
Step-by-step explanation:
The equation of a parabola in vertex form is
y = a(x - h)² + k
where (h, k) are the coordinates of the vertex and a is a multiplier
Here (h, k) = (2, - 25), thus
y = a(x - 2)² - 25
To find a substitute (7, 0) into the equation
0 = a(7 - 2)² - 25 = a(5)² - 25 = 25a - 25 ( add 25 from both sides )
25a = 25 ( divide both sides by 25
a = 1, thus
y = (x - 2)² - 25 ← in vertex form
Expand and simplify
y = x² - 4x + 4 - 25
y = x² - 4x - 21 ← in standard form