If the amount of time taken to go said distance is x and the amount of time taken to go back said distance is y, then the amount of miles total is 7x+3y due to that for every hour, she adds 7 miles when going there and 3 miles for walking back. In addition, since the total amount of time is 4 hours, x+y=4 as the total time spent as well as 7x=3y due to that they're the same distance.
x+y=4
7x=3y
Dividing the second equation by 7, we get x=3y/7. Plugging that into the first equation, we get 3y/7+y=4=10y/7 (since y=7y/7). Multiplying both sides by 7 and then dividing both by 10, we get 28/10=2.8=y in hours. Since 0.1 hours is 60/10=6 minutes, and 0.8/0.1=8, 6*8=48 minutes=0.8 hours, meaning that she should plan to spend 2 hours and 48 minutes walking back
Answer:11x + 5
Step-by-step explanation:1/3 times 9X is 3x. 1/3 times 15 is 5. Now you have 9x + 5 + 2x
9x + 2x = 11x
Final answer: 11x + 5
Answer:
9.57 inch
Step-by-step explanation:
(4/3)×pi×8³ = 14×16×h
h = (4/3)×pi×8³ ÷ (14×16)
h = 64pi/21 inch
Or, 9.57 inch (3 sf)
Simplifying
2c + 3 = 3c + -4
Reorder the terms:
3 + 2c = 3c + -4
Reorder the terms:
3 + 2c = -4 + 3c
Solving
3 + 2c = -4 + 3c
Solving for variable 'c'.
Move all terms containing c to the left, all other terms to the right.
Add '-3c' to each side of the equation.
3 + 2c + -3c = -4 + 3c + -3c
Combine like terms: 2c + -3c = -1c
3 + -1c = -4 + 3c + -3c
Combine like terms: 3c + -3c = 0
3 + -1c = -4 + 0
3 + -1c = -4
Add '-3' to each side of the equation.
3 + -3 + -1c = -4 + -3
Combine like terms: 3 + -3 = 0
0 + -1c = -4 + -3
-1c = -4 + -3
Combine like terms: -4 + -3 = -7
-1c = -7
Divide each side by '-1'.
c = 7
Simplifying
c = 7
Here we get the statement:
"sec^-1(0.5) is undefined"
And we want to see if this is true or false, so let's use the properties that we know to find that this is false.
Remember that the sec function is defined as:

Then we will have:

Then is really trivial to see that:

Then we can conclude that the function is not undefined at 0.5, so the statement is false.
Below you can see the graph of the given function, and you will see that it is never undefined.
If you want to learn more, you can read:
brainly.com/question/16453813