Answer: choice D) 20
-------------------------------
Explanation:
Locate 3 on the x axis number line. Draw a vertical line through 3 and this vertical line will cross the parabola at some point P. Mark this point P on the parabola. Then draw a horizontal line from P to the y axis. The horizontal line will land on y = 10. In short, this all shows us that (3,10) is a point on this parabola.
Repeat those steps above, but now for x = 7. You'll see that (7,90) is another point on this parabola.
We need to find the slope of the line through the two points (3,10) and (7,90). The average rate of change from x = 3 to x = 7 is the same as the slope of the line through those two points.
To find the slope, we use the slope formula
m = (y2 - y1)/(x2 - x1)
where (x1,y1) and (x2,y2) are the two points, and m is the slope
In this case,
(x1,y1) = (3,10) and (x2,y2) = (7,90)
further breaking down to
x1=3
y1=10
x2=7
y2=90
So we'll plug those four pieces of info into the equation and simplifying to get...
m = (y2 - y1)/(x2 - x1)
m = (90 - 10)/(7 - 3)
m = 80/4
m = 20
The slope of the line is 20, so therefore, the average rate of change is 20.
Answer:
Step-by-step explanation:
If slope of two lines are equal, then they are parallel lines.
If product of the slope of two lines is (-1), then they are perpendicular lines.
C) y = x + 2
Slope m1 = 1
y = -x + 3
Slope m2 = -1
m1 * m2 = 1 * (-1) = -1
These are perpendicular lines.
D) y = 3x + 2
Slope = m1 = 3
y = 3x - 2
Slope = m2 = 3
Slopes are equal. So, they are parallel lines.
E)y= 3
This line is parallel to x -axis.
x = 4
This line is parallel to y-axis.
So, both lines are perpendicular to each other.
F) y = x + 8
slope m1 = 1
y = -x + 3
Slope = m2 = -1
M1 * m2 = 1 * (-1) = -1
So, These are perpendicular lines
Answer:
Quarters = 10
Dimes = 15
Step-by-step explanation:
d = number of dimes, q = number of quarters
d + q = 25 is the equation for number of coins
0.1d + 0.25q = 4 is the equation for value of coins
First, solve for d in terms of q:
d + q = 25
d = 25 - q
Then substitute that into the other equation:
0.1(25 - q) + 0.25q = 4
2.5 - 0.1q + 0.25q = 4
0.15q = 1.5
q = 10
And back to d = 25 - q, d = 25 - 10 = 15
Check the math:
0.1(15) + 10(0.25) = 1.5 + 2.5 = 4
LMK if you have questions
Answer:
1st. associative property
Step-by-step explanation:
same order
Answer:
<em>y = $ x/3 </em>
Step-by-step explanation:
Let the amount of dollars in Teo's bank on Tuesday be $x and the amount in his bank on Friday be $y.
If the number of dollars in Teo's bank account on Tuesday was 3 times as
much as the amount on Friday, this can be represented mathematically as;
x = 3y where y is the amount in his bank on Friday.
The amount of dollars in his account on friday will be gotten by dividing both sides of the equation by 3
3y = x
3y/3 = x/3
y = x/3
<em>Hence the amount of dollars in his account on Friday is y = $ x/3 </em>
