Answer:
8
Step-by-step explanation:
Hello,
This is related to ratios and proportions. We have a 12 foot tree that casts a 6 foot shadow, so now we are trying to figure out how tall is a tree that casts a 4 foot shadow.
We can set an easier method to get this.
12 = 6 (this means the 12 foot tree casts a 6 foot shadow)
x = 4 (this means how tall is the tree to cast a 4 foot shadow, the unknown height of the tree is denoted as x)
Then, we can cross multiply.
48 = 6x
Solve for x, which is the unknown height we are trying to figure out.
x = 8
18) Value of b is : 
Option A is correct.
19) Option C is correct.
Step-by-step explanation:
18) We need to find the value of b.
The given equation is:

Solving to find the value of b:

So value of b is : 
Option A is correct.
19) We need to find the correct graph of the equation:

Solving:

The values of y will be less than three. As y < 3 so, the circle on y is not filled.
So. Option C is correct.
Keywords: Solving Inequalities
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Answer: 6
Step-by-step explanation: