Answer:
(a) Rule: Multiply the input (x) by 2 and add 5 to the result of the product
(b) 
Step-by-step explanation:
Given
The attached table
Solving (a): The rule of the table in words
First, we calculate the slope (m)

Using:


So, we have:



The equation is calculated using:

Using:

We have:


Make y the subject


Hence, the rule is:
Multiply the input (x) by 2 and add 5 to the result of the product
(b): The rule, in algebra
As solved in (a), the rule is:

Answer:
D(-7,-2)
Step-by-step explanation:
A(-4,3) B(5,-1) C(-2,-6) D(-7,-2)
A: 5×(-4) + 6×3 = -2 ≥ -30 ..... No
B: 2/3×5 + 1 =4.33 ≥ -1 ....No
C: -6 ≤ 2/3×-2 +1 ....No
D: 2/3×(-7)+1 = 2.333 ≤ -2
5×(-7) + 6×(-2) = -47 ≤ -30 ......Yes
Answer: 117.5 seconds
Step-by-step explanation:
Given : It takes you 47 seconds to walk from the first (ground) floor of a building to the third floor.
Since from first floor to third , a person need to pass two levels of staircase.
We assume that the person walk at the same pace and the height of all floors are same.
The time taken to pass each level = (Time taken to pass 2 levels) ÷ 2
= (47 seconds) ÷ (2) = 23.5 seconds
Also, the from first floor to sixth floor , a person need to pass 5 levels of staircase.
Then, the time taken to pass each level = 5 x (Time taken to pass one level)
= 5 x 23.5 =117.5 seconds
Hence, it will take 117.5 seconds to walk from the first floor to the sixth floor.
The solution of this equation is x = 5 and x = 9.
<h3>What is the solution?</h3>
Let us recall that what we have here is a radical equation as follows;
√7x+1 - √x-5 = 6
When we isolate we have';
√7x+1 = √x-5+6
Taking the square of both sides;
(√7x+1)^2 = (√x-5+6)^2
Hence;
7x+1 = x-5+36+12√x-5
-12√x-5 = -7x-1+x-5+36
12√x-5 = 6x-30
Raising this equation to power 2
144x-720 = 36x^2-360x+900
When we rearrange we obtain;
36x2 - 504x + 1620 = 0
Hence;
x = 5 and x = 9
Learn more about radical equation:brainly.com/question/8606917
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