Answer:
a=3, c=-4, x=8
Step-by-step explanation:
5=4a-7
4a-7=5
4a=5+7
=12
a=12÷4
=3
3-8c=35
-8c=35-3
=32
c=-32÷8
=-4
-1/2x-7=-11
-1/2x=-11+7
=-4
x=4÷1/2
=4/1×2/1
=8
Part A: The exponential function is the best model for the given data. The data shows that every month the number of visitor approximately doubles from previous month. In other words the number is some base value (2, in this case) with the number of month (t) being in the exponent. This the a key characteristic of an exponential growth.
Part B: (also explained above). Every month the number of visitors approximately doubles. Starting with 5.74 at month 8, the numbers goes up by about the same amount to 12.0 at month 9. At month 10, a similar increase occurs (doubling would be 24, and the data shows 25, so this is all "aproximate"). This trend continues throughout the table.
Part C:
Month 7 will be estimated as half of month 8 (going backward):
Month 7: 5.74/2=2.87
Estimate for month 7 = 2.87 thousand visitors.
Find the vertex:
Determine if the parabola will open up or down:
Since the value of a is positive, the parabola will open upwards
Find the x and y intercepts:
Factor 
to find the x intercepts
(x+8)(x+2)
x + 8 = 0
x = -8
x + 2 = 0
x = -2
x intercepts:
x = -2
x = -8
Find the y intercept
Hence, C. Graph A best represents the quadratic function
Answer:
Option b) and c) are correct
Step-by-step explanation:
Given expression is 5s - 11b + 3s - 12b
5s - 11b + 3s - 12b=8s-23b (Rearranging the right hand side terms)
5s - 11b + 3s - 12b =-23b+8s
Option c) is correct
By the definition of equivalent the given expression is the sum of the two terms ( the terms may vary or equal)
From the definition of equivalent we get, Option b) is also correct
Therefore Option b) and c) are correct
