Two correct answers:
9 + x
x + 9
Or you can say
x - -9
or
9 - -x
A circle has infinit lines of symmetry. They pass through the centre of the circle and are the circle's diameter.
Hope this helps! (:
Answer:
The value of the test statistic is 
Step-by-step explanation:
The null hypothesis is:

The alternate hypotesis is:

Our test statistic is:

In which X is the sample mean,
is the null hypothesis value,
is the standard deviation and n is the size of the sample.
In this problem:

So



The value of the test statistic is 
Step-by-step explanation:
x =7y ----(1)
xy=252 ----(2)
(1) into (2):
(7y)(y) = 252

7y=15.874....
y=2.27
y value into (1)
x= 7(2.268)
x=15.87
the two numbers are 15.87 and 2.27 (Ans)