Answer:
x = 8
Step-by-step explanation:
Equilateral triangle : congruent angles
3(7x+4) = 180
21x + 12 = 180
21x = 180-12
x = 168/21
x = 8
Answer:
x = -3
y = -8
Step-by-step explanation:
2y = x - 13
3x = y - 1; let y = 3x + 1
substitute to solve for 'x':
2(3x + 1) = x - 13
6x + 2 = x - 13
5x + 2 = -13
5x = -15
x = -3
solve for 'y':
3(-3) = y - 1
-9 = y - 1
-8 = y
Answer:
x=-400
x=-95
Step-by-step explanation:
They are negative because a negative times a negative is a positive.
The value that is 2 standard deviations from the mean is; 130
<h3>What is Empirical Rule?</h3>
For this question, we will use Z-score and as such whether the value is below or above mean (shown by positive or negative sign) and by how much (times the standard deviation).
Thus;
Calculated value = μ + zσ
where;
μ is mean
σ is standard deviation
Hence, the value that would be +2 standard deviations from the mean is;
Calculated value = 100 + 2(15)
Calculated value = 130
Read more about Empirical Rule at; brainly.com/question/10093236
