Answer:
A.) 2x - 9x - 30 = -6
Step-by-step explanation:
hello !
to solve this system of equations, first, we substitute the equation
to the <em>y </em>variable in the equation
. Therefore, we get:

now, we simplify by multiplying -3 to the variables inside the parenthesis, which, in short, is also called the distributive property. thus, we get:

Answer:
The measure of the third arc is 
Step-by-step explanation:
step 1
we know that
The measurement of the external angle is the semi-difference of the arcs which comprises
in this problem
Let
x----> the greater arc of the circle intercepted by the secant and the tangent
y----> the smaller arc of the circle intercepted by the secant and the tangent

----> equation A

-----> equation B
Substitute equation B in equation A and solve for y

Find the value of x

step 2
Find the measure of the third arc
Let
z------> the measure of the third arc
we know that
-----> complete circle
substitute the values and solve for z


Answer:
I found x for you, right there.
Answer:
$301 - $397
Step-by-step explanation:
Using the Empirical rule
1) 68% of data falls within 1 standard deviation from the mean - that means between μ - σ and μ + σ .
2)95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ .
3)99.7% of data falls within 3 standard deviations from the mean - between μ - 3σ and μ + 3σ .
From the above question,
Mean = 349 , standard deviation = 24.
Confidence interval = 95%
Using 2)95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ .
μ – 2σ
= 349 - 2(24)
= 349 - 48
= 301
μ + 2σ
349 + 2(24)
= 349 + 48
= 397
Therefore, according to the standard deviation rule, approximately 95% of the students spent between $301 and $397 on textbooks in a semester.