Answer: a) 15625, b) 0.2, c) 625, d) 0.008.
Step-by-step explanation:
Since we have given that
a) 
As we know that

So, it becomes,

(b) 
So, it becomes,

(c) 
As we know that

So, it becomes,

(d) 

Hence, a) 15625, b) 0.2, c) 625, d) 0.008.
Hey there!
First, multiply the second equation by -2 as the problem states. When you multiply the second equation by -2, you get:
-2x+4y=2
Now, add this equation to the first equation in which you simply combine like terms:
2x+y=3
+
-2x+4y=2
=
5y= 5
In conclusion, the correct answer would be the first choice.
Answer:
The answer is to the question is 13
Answer:
5
Step-by-step explanation:
To obtain the total score for all the 20 students, we multiply the average score by the number hence
Total score for all 20 is 81*20=1620
Similarly, for the 19 students, the sum of their total score equals the product of the average and number of students hence
Total score for 19 readable is 19*85=1615
The difference between these two total scores ie for 20 and 19 students equals to the value of unreadable score. Therefore,
Difference=1620-1615=5
Therefore, the value of unreadable score is 5
A circle with center
and radius
has equation

If we substitute
in this equation, we have

This equation has two solutions (i.e. the line intersects the circle in two points) if and only if the determinant is greater than zero:

The expression simplifies to

The solutions to the associated equation are

So, the parabola is negative between the two solutions:
