Well, we can input both variables to check and see if the numbers hold.
-691 = -51(-15) - 74
-691 = 765-64
-691 = 701
(-15, -691) does not make the equation true.
Real numbers, both rational and irrational numbers are real numbers
Answer:
The correct answer is: Option D) 5
Step-by-step explanation:
Given equation is:

In order to find that which values of x makes the equation true, we have to put each value of x in the equation. When both sides of equations will be equal, that value of x will be true for the equation.
Putting x = 2

Putting x = 3

Putting x=4

Putting x = 5

The equation is true for x = 5
Hence,
The correct answer is: Option D) 5
Answer:
66
Step-by-step explanation:
Use the formula for the mean of a set of numbers:
sum of the numbers
average = --------------------------------
count of numbers
Here we know that the average mark was 68, so we can write:
75 + 62 + 84 + 53 + x
average = 68 = ----------------------------------
5
or 274 + x
68 = -------------------
5
Solving for x, we multiply both sides by 5: 340 = 274 + x.
Subtracting 274 from both sides effectively isolates x:
340 = 274 + x
- 274 -274
------------------------
66 = x
The fifth student's mark was 66.