Answer:
The expression for the nth term is Tn = 8n -7
Step-by-step explanation:
Here, we are to find an expression for the nth term of the sequence.
Mathematically, the nth term of an arithmetic sequence can be expressed as;
Tn = a + (n-1)d
for T2, the equation is
a + d = 9
for T4, the equation is
a + 3d = 25
we can substitute the equation of T2 into T4 but we first need to rewrite T4
a + d + 2d = 25
9 + 2d = 25
2d = 25 -9
2d = 16
d = 16/2
d = 8
now since a + d = 9
a = 9-d
a = 9-8
a = 1
So the expression for the nth term would be;
1 + (n-1)8
1 + 8n - 8
= 8n -8+1
= 8n -7
According to the empirical rule, roughly 68% of the scores fall between z = -1 and z = 1
You can use a calculator to get a more approximate answer. If you have a TI calculator, you can use the "normalcdf" function to type in normalcdf(-1,1)
Equation : (7x-4)+(3x-3)+(x) = 180
In the equation the sum of the internal angle in the triangle is 180 degrees. Use this equation to figure the sum of angle in any quadrilateral 180*(number of sides-2)
Solve the equation
Put all similar variable on one side
7x+3x+x-4-3=180
11x-7=180
11x=180+7
11x=187
x = 187/11
x = 17
Now find the angles by plugging in x
Angle F (7*17-4) = 115 degrees
Angle G (x) = 17 degrees
Angle E (3*17-3) = 48 degrees
If you add 115+48+17 you will get a sum of 180 this shows your answer is right
Angle F = 115
Angle G = 17
Angle E = 48
C=300+1200x-100x. Find x if the total cost is 3,000
3,000 = 300 + 1200x -100x
3000 = 300 + 1100x
2700 = 1100x
2700÷1100=x
x=27/11
x = 2 5/11
Round to 3