What's happening is that every subtraction can be written as "addition of the opposite."
18-5 = 18 + (-5)
One reason this is done in the work you showed is that they're trying to show why you distribute the negative and the 1 into the parentheses, why you multiply everything in the parentheses by "-1" and not just 1.
The other reason is to later to be able to move the individual terms around, so you'll be able to combine like terms.
When you move terms around, the sign has to stay attached to the term, so writing all the subtractions as addition helps keep the sign attached.
Answer:
10 years
Step-by-step explanation:
the average or mean value is the sum of all data points divided by the number of data points.
x = the unknown age of the 5th student.
average = 9 = (5 + 7 + 8 + 15 + x)/5
45 = 5 + 7 + 8 + 15 + x = 35 + x
x = 45 - 35 = 10
the 5th student is 10 years old.
Answer:
0.41666666, to round up, the answer is 0.42
Step-by-step explanation:
Answer:
The equation in the standard form is
Step-by-step explanation:
Given the points
Finding the slope between (6, -7) and (4, -3)
As the point-slope form is defined as
substituting the values m = -2 and the point (6, -7)
Writing the equation in the standard form form
As we know that the equation in the standard form is
where x and y are variables and A, B and C are constants
converting the equation in standard form
subtract 7 from both sides
Therefore, the equation in the standard form is
