Okay, well we start out with the equation P=66, where P is perimeter. You should create equations using variables to explain each piece of information you are given. Follow the equations below and see if you can understand how to do another one like this. In this problem, l is length and w is width.
P = 66 The perimeter is equal to 66
l = 3 + w The length of one side is 3 more than the width
2l + 2w = 66 A rectangle's perimeter is calculated by adding the lengths and widths
2(3 + w) + 2w = 66 Use what you know about length from step 2 to replace the variable in step 3
6 + 2w + 2w = 66 Multiply
6 + 4w = 66 Add like terms
4w = 60 Subtract
w = 15 Divide
l = 3 + w Remember step 2?
l = 3 + 15 Replace the variable using your value for w
l = 18 Add
And you're done! Always check your work. It helps to create a picture of a rectangle while you're doing these problems as well. As you get used to these problems more and more, you can show more or less work than I've shown, but try to stay true to what the teacher asks of you. Good luck!
Answer:
<u>The correct answer is D. Any amount of time over an hour and a half would cost $10.</u>
Step-by-step explanation:
f (t), when t is a value between 0 and 30
The cost is US$ 0 for the first 30 minutes
f (t), when t is a value between 30 and 90
The cost is US$ 5 if the connection takes between 30 and 90 minutes
f (t), when t is a value greater than 90
The cost is US$ 10 if the connection takes more than 90 minutes
According to these costs, statements A, B and C are incorrect. The connection doesn't cost US$ 5 per hour like statement A affirms, the cost of the connection isn't US$ 5 per minute after the first 30 minutes free as statement B affirms and neither it costs US$ 10 for every 90 minutes of connection, as statement C affirms. <u>The only one that is correct is D, because any amount of time greater than 90 minutes actually costs US$ 10.</u>
= 6.37 * 10^4 = 637 * 10^2 = 63700
In short, Your Answer would be Option A
Hope this helps!
Assuming you mean y=10x+150 and y=20x+115, you need to use a simultaneous equation, because you have two equations with two unknowns (x and y)
rearrange so
10x-y=-150
20x-y=-115
multiply the top by -1, so that if we add the two lines together, the y will cancel out
-10x+y=150
20x-y=-115
add the two lines together
10x=35
x=3.5
so the time is 3 and a half weeks
then we can sub in x to find y
20x-y=-115
20(3.5)-y=-115
70-y=-115
-y=-185
y=185
so 185 tickets were sold !
you can sub these values into your original equations to check your answer :)
