He donated 18 books per month. you first finds the difference of the books then do use the number of books by the number of months (in this case it was 5 months)
Answer:
x = 9
Step-by-step explanation:
1) Subsitute! You have to replace y with 2x - 2 in 3x -y = 7, b/c they already gave you the equation for y (in the second part: y = 2x - 2)
So, your equation would look like this : 3x - (2x - 2) = 7
3) Solve suing PEMDAS!
There's a negative outside the parenthesis of 2x -2 -> - (2x-2). Multiply the negative individually inside the parenthesis so you will get (-2x + 2)
3x - 2x - 2 = 7 subtract the same variable; x
1x - 2 = 7 you don't need to put 1 to x, only if you want!
+ 2 + 2 add 2 on both sides
x = 9
<h3>
Answer: 0.8790072 approximately</h3>
Round this however your teacher instructs.
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Work Shown:
mu = 830 = mean
sigma = 96.7 = standard deviation
x = 915 = given raw score we want to convert
z = (x - mu)/sigma
z = (915 - 830)/(96.7)
z = (85)/(96.7)
z = 0.8790072 approximately
Answer:
the answer is 23.
Step-by-step explanation: 20/15=1.5333333333......=1 1/2
Step-by-step explanation:
6x + 21y = 103
-6x + 23y = 51
The signs of the x coefficients are opposite. So adding the equations will eliminate the x terms.
44y = 154
y = 3.5