Answer:
Equivalent expressions
A) 
C) 
Step-by-step explanation:
Given expression :

Choices given :
A) 
B) 
C) 
D) 
To find the equivalent expression.
We will first evaluate the given expression.

⇒
[Quotient of a negative dividend and a positive divisor is always negative]
Evaluating each choice to select the equivalents.
A) 
⇒
[Quotient of a positive dividend and a negative divisor is always negative]
B) 
⇒ 
⇒ 
C) 
⇒
[Product of a positive and a negative is always a negative]
⇒ 
D) 
⇒
[Product of two negatives is always a positive]
⇒ 
∴ We see that the choices A and C are equivalent.
Answer:
The value is 
Step-by-step explanation:
From the question we are told that
The sample size is n = 20
The sample mean is 
The standard deviation is 
Generally the standard error of the mean is mathematically represented as

=> 
=> 
Answer:
-3x² +6x -1 = 0
Step-by-step explanation:
x2 - 2x + = 4(x2-2x +1)-3
x² - 2x = 4x²-8x +4 - 3
x²-4x²-2x+8x = 4-3
-3x² +6x = 1
-3x² +6x -1 = 0
After reading the problem, you are often asked to solve it.
Complementary angels add up to 90°
so x+18°=90°
so x=90-18=72°