Answer:
The Standard Deviation is a measure of how spread out numbers are. You might like to read this simpler page on Standard Deviation first. But here we explain the formulas. The symbol for Standard Deviation is σ (the Greek letter sigma)
Answer:
x = 1 or x = -5
Step-by-step explanation:
We are given;
- The quadratic equation, x² + 4x - 13 = -8
We are required to solve the equation using the completing square method.
To do this, we use the following steps;
Step 1: We make sure the coefficient of x² is one
x² + 4x - 13 = -8
Step 2: Combine the like terms (take the constant term to the other side)
x² + 4x - 13 = -8
x² + 4x = -8 + 13
we get
x² + 4x = 5
Step 3: We add the square of half the coefficient of x on both sides of the equation
Coefficient of x = 4
Half of coefficient of x = 2
Square of half the coefficient of x = 2² (4)
We get;
x² + 4x + (2²) = 5 + (2²)
Step 4: Put x and 2 under one square and the solve the other side of the equation.
We get
(x + 2)² = 5 + 4
(x + 2)² = 9
Step 5: Get the square root on both sides of the equation;
(x + 2)² = 9
√(x + 2)² = ±√9
(x + 2)= ±3
Therefore;
x+2 = + 3 or x + 2 = -3
Thus, x = 1 or -5
The solution of the equation is x = 1 or x = -5
Answer:
C-17 I think my bad
Step-by-step explanation:
