I would do it this way
$780+$225=$1005
$1005/120ft= $8.375
if you have to round up $8.38 per foot
Both elevations or numbers are already expressed as a
rational number. This is because a rational number is defined as a number that
can be expressed as a quotient or fraction of two numbers:
p / q
Since in this case, q may be equal to 1, then both are
rational numbers.
Answer: 6.71
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Work Shown:
The longest horizontal portion of length 6 breaks up into two equal pieces of length 3 each. Focus on the smaller right triangle on the right hand side. This right triangle has legs of 3 and 6. The hypotenuse is x.
Use the pythagorean theorem with a = 3, b = 6, c = x to find the value of x
a^2 + b^2 = c^2
3^2 + 6^2 = x^2
9 + 36 = x^2
45 = x^2
x^2 = 45
x = sqrt(45)
x = 6.7082039
x = 6.71
Add all three expressions up and set them equal to 180 degrees, because there are 180 degrees in a triangle.