Answer: 
Step-by-step explanation:
Let A = he known the answer then A' = he guess the answer.
B = he answered it correctly
As per given , we have



By Bayes theorem , we have

The probability that the student knows the answer given that he answered it correctly is
.
4x² - 16 is the algebraic expression that must be added to get the result as 9x²- 2x - 5.
<u>Step-by-step explanation:</u>
The question is asked for the algebraic expression must be added to the sum of 3x²+4x+8 and 2x2−6x+3 to give 9x²- 2x - 5 as the result.
Therefore,
The first step is to find of sum of 3x²+4x+8 and 2x²-6x+3.
To find the sum :
3x²+4x+8
<u>2x²-6x+3 </u>
<u>5x²-2x+11</u>
The sum is 5x²-2x+11.
Now, the second step is to subtract 5x²-2x+11 from the result 9x²- 2x - 5.
9x²- 2x - 5
- <u>(5x²-2x+11)</u>
<u> 4x² -16 </u>
Thus, 4x²-16 is the algebraic expression that must be added with 5x²-2x+11 to get a result of 9x²- 2x - 5.
Answer:
The dimensions of the rectangle are length = 7cm and width = 6cm.
Step-by-step explanation:
In order to solve for the dimensions, you will need to set up two equations in order to solve for the missing variable. Given the information that the length is 5 cm less then twice it's width, using 'L' for length and 'w' for width we get the following equation: L = 2w - 5. Perimeter is the sum of all the sides, or in the case of a rectangle P = 2w + 2L. We can then use our expression for 'L' in our perimeter formula: 26 = 2w + 2(2w - 5). First, using the distributive property we get: 26 = 2w + 4w - 10. Next, we combine like terms: 26 = 6w - 10. Then, we use inverse operations to isolate the variable: 26 + 10 = 6w - 10 + 10 to get 36 = 6w, divide both sides by 6 to get w = 6. Lastly, plug in the value of 'w' to 'L': L = 2(6) - 5 or L = 7.
Answer: 54%
Step-by-step explanation:
24+17+5=46
100-46=54
To do this you can do (pay) x (hours) to work out how much Johnny makes for example:
8.25 x 29.5 = 243.375$ so the answer is 243.375$