Answer:
B
Step-by-step explanation:
Mathematically, we shall be using the z-score here
Z-score = (x-mean)/SD
From the question, mean = 80 and SD = 4
So we want to get the option in the question that has a z-score of 1 or below
Let’s look at 75
80-75 = 5 ( this is clearly above 1 standard deviation of 4)
For 77;
80 -77 = 3
This is less than the standard deviation of 4, meaning it is within 1 standard deviation of the mean
Incorrect, she should have divided both sides by 8. The answer should be x=7. There is only 1 solution to the equation because x is raised to the first degree. It is not a polynomial equation so there won't be more than 1 answer to the equation.
Answer:
30-100/1000*120
Step-by-step explanation:
Source: Khan Academy
Answer: Adiya’s method is not correct. To form a perfect square trinomial, the constant must be isolated on one side of the equation. Also, the coefficient of the term with an exponent of 1 on the variable is used to find the constant in the perfect square trinomial. Adiya should first get the 20x term on the same side of the equation as x2. Then she would divide 20 by 2, square it, and add 100 to both sides.