Answer:
Step-by-step explanation:
log 2.5=log 21/2=log (3*7)/2=log3+log7-log 2=0.48+0.85-0.3=1.03
Answer:
4
Step-by-step explanation:
Equation 1
Equation 2
What is the value of 
where each variable represents a real number?
Let's expand equation 1:
Simplify each term if can:
See if we can factor a little to get some of the left hand side of equation 2:
The first two terms have 
and if I factored from first two terms I would have 
which is the first term of left hand side of equation 2.
So let's see what happens if we gather the terms together that have the same variable squared together.
Factor the variable squared terms out of each binomial pairing:
Replace the sum of those first three terms with what it equals which is 6 from the equation 2:
Combine like terms:
Subtract 6 on both sides:
Divide both sides by 3:
<span>The parent cosine function can be transformed and translated. So, from the basic function cos(x) we can obtain function acos(bx+c). In our case, a=3- amplitude, b=10- the period change and c=-pi- the phase shift. So, the parent cosine function is mutiplied with 3 (which gives the amplitude of the function, 3*0.5=1.5). The period of the function is changed, and is 2pi/b=2pi/10=pi/5 and the cos(x) is phase shifted for c/b=-pi/10.</span>
Answer: point estimate = 3.88
Margin of error = 0.63
Step-by-step explanation:
Confidence interval is written in the form,
(Point estimate - margin of error, Point estimate + margin of error)
The sample mean, x is the point estimate for the population mean. Let m represent the margin of error. Since the confidence interval is given as (3.25 , 4.51), it means that
x - m = 3.25
x + m = 4.51
Adding both equations, it becomes
2x = 7.76
x = 7.76/2
x = 3.88
Substituting x = 3.88 into x + m = 4.51, it becomes
3.88 + m = 4.51
m = 4.51 - 3.88
m = 0.63
Answer:
Step-by-step explanation:
-7x + 12 + (-8x + 48) = 180
-15x + 60 = 180
-15x = 120
x = -8
m<BDC= -7(-8)+ 12 = 56 + 12 = 68
m<CBA = -8(-8)+48 = 64+48 = 112
