Answer:
A. add 81; 
Step-by-step explanation:
The perfect square formula

Rewrite expression
as follows:

So, to form a perfect square,
is missed.
When we add
we will get

Answer:
We have been given the equation:

And x=10
Substitute the given x in the given equation we get:


On simplification we get:

Required solution is: x= 10 and y=-20
The solution to the system of equation is those points that satisfy the given system of equations.
Keeping in mind that "dx" is the delta x, or differential over the x-axis, whilst "dy" is the delta y or differential over the y-axis,
You're trying to find constants

such that

. Equivalently, you're looking for the least-square solution to the following matrix equation.

To solve

, multiply both sides by the transpose of

, which introduces an invertible square matrix on the LHS.

Computing this, you'd find that

which means the first choice is correct.
Answer:
(IQR) interquartile range = 5
Step-by-step explanation:
Lower quartile: 48
Upper quartile: 53
Median: 52
Lowest value: 46
Highest value: 55
(IQR) interquartile range: Upper quartile - Lower quartile = final answer
(IQR) interquartile range: 53 - 48 = 5