Answer:
Cartesian plane
Step-by-step explanation:
(–1 , 3)
D because a has to be younger than 18 and it has to be positive because we are never a negative age. do you understand when i mean?
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Answers:
1) 

2) 
Step-by-step explanation:
In mathematics there are rules related to complex numbers, specifically in the case of addition and multiplication:
<u>Addition:
</u>
If we have two complex numbers written in their binomial form, the sum of both will be a complex number whose real part is the sum of the real parts and whose imaginary part is the sum of the imaginary parts (similarly as the sum of two binomials).
For example, the addition of these two binomials is:

Similarly, the addition of two complex numbers is:
Here the complex part is the number with the 
<u>Multiplication:
</u>
If we have two complex numbers written in their binomial form, the multiplication of both will be the same as the multiplication (product) of two binomials, taking into account that
.
For example, the multiplication of these two binomials is:

Similarly, the multiplication of two complex numbers is:
Answer:
-3
Step-by-step explanation:
Here is a different example.
'm' is the gradient (or slope). We measure the difference between the two x values and two y values to see how each of them changed respectively. We know m = rise/run so we can put in our slope (7) and points to find t.
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