Answer: 2 / 5x
Explanation:
So,
All you have to do is to translate the words into open sentences with placeholders.
Apparently, there are 2 numbers, call them x and y.
Now, build open sentences.
x + y = 12
x - y = 4
Now, which method will we use to solve? I choose Elimination by Addition.
Add the equations together.
2x = 16
Divide both sides by 2
x = 8
Substitute
8 + y = 12
Subtract 8 from both sides.
y = 4
Check
The sum of the two numbers is 12 (8 + 4).
The difference of the two numbers is 4 (8 - 4).
The first number is 8.
The second number is 4.
Answer:
Philadelphia to Gettysburg.
Step-by-step explanation:
For Allentown to Gettysburg, the drive is
1hour= 55m
1m = hour
= 0.018 hour
For Philadelphia to Gettysburg, the drive is
1 hour = 65m
1m = hour
= 0.015 hour
For Reading to Gettysburg, he drive is
1 hour= 40m
1 m = hour
= 0.025 hour
Therefore, Philadelphia to Gettysburg has shorter drive in hours that is 1 metre is travelled in 0.015 hours
<h3>
Answer: D) 18</h3>
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Work Shown:
Here are the variables we're working with
- a = first term
- b = last term (aka nth term)
- n = number of terms
- S = sum of the first n terms
In this case, we know that
- a = unknown (what we want to solve for)
- b = -12
- n = 14
- S = 42
We can use this formula to help find the answer
S = (n/2)*(a+b)
This formula only works for arithmetic sequences
So,
S = (n/2)*(a+b)
42 = (14/2)*(a+(-12))
42 = 7(a-12)
42/7 = a-12
6 = a-12
6+12 = a
18 = a
a = 18 is the first term of this arithmetic sequence
That's why the answer is choice D.
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Side note: your book or your teacher may use the notation but I figured it would be easier to use 'a' and b in place of and respectively.