I'm not sure but I think it is the first one
Answer:
10x +3x are like terms
5+1 is terms
Step-by-step explanation:
Answer:
85%
Step-by-step explanation:
The discount is 15% which we can write as 0.15 and we multiply that by 30 to get the discount, which is $4.50. We subtract that from the original price; 30 to get $25.50 as the sale price. We want to find out what percent of 30 25.50 is, so we divide 25.50 and 30 to get 0.85. Multiply that by 100 to get 85%.
Answer:
- <u>The rate of return is 8.15%</u>
- <u>This is a good investment</u>
<u></u>
Explanation:
For the first question, you need to find the rate that makes the present value of a stream of ten constant annual payments of $15,000 equal to the $100,000 investment.
The formula that returns the present value of a constant payment is called the annuity formula and is:
![Present\text{ }value=payment\times \bigg[\dfrac{1}{r}-\dfrac{1}{r(1+r)^t}\bigg]](https://tex.z-dn.net/?f=Present%5Ctext%7B%20%7Dvalue%3Dpayment%5Ctimes%20%5Cbigg%5B%5Cdfrac%7B1%7D%7Br%7D-%5Cdfrac%7B1%7D%7Br%281%2Br%29%5Et%7D%5Cbigg%5D)
In your problem you know:
- Present value: $100,000
- payment: $15,000
- r: ?
- t: 10
You cannot solve for r directly. You must guess a value and calculate the right side of the equation until to you find the rate that makes it equal to 100,000.
Try 5%:
![\$15,000\times \bigg[\dfrac{1}{0.05}-\dfrac{1}{0.05(1+0.05)^{10}}\bigg]=\$115,826](https://tex.z-dn.net/?f=%5C%2415%2C000%5Ctimes%20%5Cbigg%5B%5Cdfrac%7B1%7D%7B0.05%7D-%5Cdfrac%7B1%7D%7B0.05%281%2B0.05%29%5E%7B10%7D%7D%5Cbigg%5D%3D%5C%24115%2C826)
Then, the rate of return is greater than 5%. After several trials you will find that the rate of return is 8.15%.
Since this rate is higher than 8%, which is what the company requires, this is a good investment.
Assume the parabola is placed on a graph where the x-axis is the top of the dish.
The vertex is then at (0,-30) The x-intercepts or zeros are at (-30,0) and (30,0)
The equation of such parabola would be:

Plug in vertex to find value of 'a'

Now find the focus given that


Answer: the microphone should be placed 7.5 inches from vertex.