Answer:

Step-by-step explanation:

Let's solve the second equation for a to later on replace it in the first equation.

Now plug this into the first equation.

Distribute the 9

Break down the fraction.

Simplify.

Subtract 

Combine like terms.



Muliply by the reciprocal or inverted fraction next to b.


Now plug this value into any of the equations to find the value of a.

Answer:
Step-by-step explanation:
A Chi-square test is used to test the test of independence between rows and columns, contingency tables. It is a test related to frequencies. The observed frequency is a given statistical frequency known as the actual frequency, the expected frequency is known as the theoretical frequency is derived from the study by using the sum total of the row and total in the column divided by their corresponding sample size.
The equation is 
<u>Explanation:</u>
We have to first find the mid-point of the segment, the formula for which is

So, the midpoint will be 
= 
It is the point at which the segment will be bisected.
Since we are finding a perpendicular bisector, we must determine what slope is perpendicular to that of the existing segment. To determine the segment's slope, we use the slope formula 
The slope is
= 
Perpendicular lines have opposite and reciprocal slopes. The opposite reciprocal of
is 
To write an equation, substitute the values in y = mx + c
WHere,
y = -1
x = 3
m = 3/2
Solving for c:

Thus, the equation becomes:

Answer:
-0.5
Step-by-step explanation:
Use the average formula:
Sum of all numbers/Number of items
6 + (-7) / 2
= -1/2
So, the number in the middle of -7 and 6 is -0.5