Answer: 2(x+y)-25
Step-by-step explanation:
First, we need to show the sum of Roger and Olivia's heights. If Roger is x and Olivia is y, the sum is <em>x+y</em>
Next, we need to double that. To double something we multiply it by 2. Since we need double the expression we found above, we put it in parentheses. So the doubled sum is shown as <em>2(x+y)</em>
Finally, we need to show that Isabella is 25 centimeters shorter than the doubled sum. To do that, subtract 25.
The final expression for Isabella's height is 2(x+y)-25
Answer:
74%
Step-by-step explanation:
We have been given that the Average cost of a long distance call in the USA was 31 cents per minute in 1978 and 8 cents in 2008.
We will use percent decrease formula to solve our given problem.






Therefore, there is an approximate 74% decrease in cost per minute for the long distance call from 1978 to 2008.
The top portion of this graph would be y = 4
The bottom portion would be y = x - 1
In order to find both of these, we have to look at them separately. Let's start with the flat line between 1 and -1. Since it is between those numbers, we know this one goes on top. We also know that since the line is horizontal, that the equation must be y = the number that it sits at. This is the definition of a horizontal line. Since the line is at 4, we get y = 4.
For the sloped portion, we have to pick two points and find the equation of the line. Let's use (3, 2) and (5, 4). We must start by finding slope (m)
m = (y1 - y2)/(x1 - x2)
m = (4 - 2)(5 - 3)
m = 2/2
m = 1
So we know slope to equal 1. Now we can use a point and slope intercept form to find the y-intercept (b)
y = mx + b
4 = 1(5) + b
4 = 5 + b
-1 = b
Now put them together in an equation for the bottom part: y = x - 1
Answer:
<em>1.5880 × 10¹.</em>
Step-by-step explanation: