Answer: 
Step-by-step explanation:
To find the equation from a graphed function, you can substitute points into each equation to find the original:
A point on the graph is (2, 4). Substituting this into each equation, we get:
, which claims that 4 is equal to 30, which is incorrect.
, which claims that 4 is equal to 3/2, which is incorrect.
, which claims that 4 is equal to 4, which is correct.
We can test the third function further by taking another point on the graph, (3, 5), and substituting it into the function:
, which claims that 5 is equal to 5, which is correct.
Answer:
<em>5 ≤ 4x - 2.5</em>
Step-by-step explanation:
<u>Inequalities</u>
The expression "no greater than" can be better expressed as "less or equal than".
The expression 4 times a number, being x the unknown number can be written: 4x
Thus, the equivalent inequality of the sentence is:
5 ≤ 4x - 2.5
Height of the woman = 5 ft
Rate at which the woman is walking = 7.5 ft/sec
Let us assume the length of the shadow = s
Le us assume the <span>distance of the woman's feet from the base of the streetlight = x
</span>Then
s/5 = (s + x)/12
12s = 5s + 5x
7s = 5x
s = (5/7)x
Now let us differentiate with respect to t
ds/dt = (5/7)(dx/dt)
We already know that dx/dt = 7/2 ft/sec
Then
ds/dt = (5/7) * (7/2)
= (5/2)
= 2.5 ft/sec
From the above deduction, it can be easily concluded that the rate at which the tip of her shadow is moving is 2.5 ft/sec.
When I put it in my calculator I got d=5
