Answer:
25x^2 -1
Step-by-step explanation:
If you multiply parentheses:
(5x*5x) + (5x*-1) + (1*5x) + (1*-1)
25x^2 - 5x + 5x -1
25x^2 -1
A simpler way is to memorize this formula
(Square1 - square2)= (sqrt of square1- sqrt of square2)*(sqrt of square1 + sqrt of sqaure2)
Find the mean, median, and mode of the data set. Round to the nearest tenth. 15, 13, 9, 9, 7, 1, 11, 10, 13, 1, 13 mean = 8.5, m
jasenka [17]
Answer:
Mean = 9.3
Median = 10
Mode = 13
Step-by-step explanation:
To get the mean, you would have to add up all of the numbers (102), then divide how many numbers you have with the numbers added up (9.3). To get the median, you would have to put all of the numbers that you have, in order, from least to greatest and cross off each number, one from each side before getting to the number in the middle (unless if you have an even number; works better with odd numbers, which is easier). To get the mode, you would need to find out which number appears the most, and, if there is more than one, you can put the numbers down. Hope this helps.
<h2>
Answer with explanation:</h2>
Let x denotes the number of days and y denotes the total change in gas price ( in dollars).
Given : During the past seven days the price of regular gas is decreased by $0.2 each day.
Rate of decrease =$0.2 per day
Then , Total change in gas price = Rate of decrease x Number of days
i.e.
i.e. 
(1)
To find the total change in gas price in 7 days , we put x= 7 in (1) , we get
Hence, the total change in gas price in 7 days = $1.4
40%
The probability of her getting a red marble is the number of red marbles divided by the number of total marbles. Since she picked a green marble first, we must subtract one marble from the total number of marbles, so that the total # of marbles is 6 + 6 + 4 = 16 - 1 (green marble) = 15. Since there are 6 red marbles, our probability is 6/15 or 2/5. Converted to percentage form, this is 0.4 —> 40%
