Answer:
Step-by-step explanation:
The worth of the card =$75
The value of the card decreases after each music purchase forming a sequence:
75,74.11,73.22,72.33...
Now,
- 74.11-75=-0.89
- 73.22-74.11=-0.89
- 72.33-73.22=-0.89
We see that the sequence forms an arithmetic sequence:
Where the first term, a is 75
Common difference, d=-0.89
We want to write an equation to define A(n), the amount of money on the gift card after n song purchases.
For an arithmetic sequence,the nth term A(n)=a+(n-1)d
Therefore:
The amount of money on the gift card after n song purchases.
A(n)=75-0.89(n-1)
A(n)=75+0.89-0.89n
A(n)=75.89-0.89n
To find out how many songs can Josh purchase with this card only, we take our nth term A(n) of the sequence to be 0 and solve for n.
A(n)=75.89-0.89n
0=75.89-0.89n
0.89n=75.89
Divide both sides by 0.89
n=85.3
n=85
Therefore, Josh can purchase 85 songs with this card only
Answer:
To be honeest i dont know
Step-by-step explanation:
Answer:
The median is 2.65 seconds
Step-by-step explanation:
So the median is the middle number. First of all, we have to sort them into ascending order.
2.35, 2.38, 2.43, 2.65, 2.69, 2.78, 10,91.
Since this is median and not mean, we don't need to get rid of outliers / anomalies.
The middle number in that would be 2.65.
Answer:
x = 8, and y = 12
Step-by-step explanation:
There are 2 variables, so you need 2 equations to form a system of equations in two variables.
The upper left triangle has all angle measures given: 100, 2x + y, 5x + y. We know that the sum of the measures of the angles of a triangle is 180.
First equation:
100 + 2x + y + 5x + y = 180
Simplify:
7x + 2y = 80 (First equation)
Now we see that the upper and lower sides are parallel, so alternate interior angles are congruent. The angles measuring 2x + y and 5x - y are alternate interior angles and are congruent.
Second equation:
2x + y = 5x - y
Simplify:
3x - 2y = 0 (Second equation)
Now we use the first equation and the second equation as a system of simultaneous equations to solve for x and y.
7x + 2y = 80
3x - 2y = 0
Solve the second equation for 2x.
3x = 2y
Now replace 2y in the first equation with 3x.
7x + 3x = 80
10x = 80
x = 8
Replace x with 8 in the second equation.
3(8) - 2x = 0
24 = 2x
x = 12
Answer: x = 8, and y = 12
In right angle triangle cot(x) = base÷perpendicular
~ 5/12