<u>Answer</u>:
x = 7, y = 2
<u>Explanation</u>:
equations given:
x + 7y = 21
x + 4y = 15
make "x" the subject:
x + 7y = 21
x = 21 - 7y .........equation 1
x + 4y = 15
x = 15 - 4y .......equation 2
Solving both the equations simultaneously:
15 - 4y = 21 - 7y
-4y + 7y = 21 - 15
3y = 6
y = 6 ÷ 3
y = 2
If y is 2
Then x = 21 -7y;
x = 21 - 7(2)
x = 21 - 14
x = 7
I'm assuming you mean
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we can factor that sum of perfect cubes from
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into
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so therefor
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that is simpliest form
The answer is 41 miles
Imagine the diagonal distance is called c
Using Pythagorean theorem 40^2 + 9^2 = c^2
1600 + 81 = c^2
The square root of 1681 is 41
So c = 41
The answer is Stan twiceushisnsskkemr