Answer:
8 ft²
Step-by-step explanation:
Since ΔEFG ~ ΔABC, they are proportionately related. Each of the corresponding sides differ by the scale factor, which shows how much bigger or smaller the new triangle is from the original triangle.
Purple = original triangle, triangle 1
Pink = new triangle, triangle 2
Find the scale factor, "k". It will be a fraction because the triangle gets smaller.
k = FG/BC = 2/3
The scale factor can be used to find a side, the height or the area of the new triangle.
Use the scale factor squared to find the area.
A₂ = (A₁)(k²)
= (18 ft²)(2/3)²
= 7.999...ft²
= 8 ft²
Of these choices, the best is the last:
run 1/rise 1 = run 2/rise 2
_____
While this will show the slope is the same everywhere, it does so by actually showing the inverse of the slope is the same everywhere. Slope is defined as
slope = rise/run
