The value of x for these stairs built by using the recommended riser-to-tread ratio is 32.5°.
Given the following data:
In Mathematics, a tread refers to the horizontal part of a step while a riser is the vertical part of a step.
Note: Let the angle of inclination be x.
In Geometry, two (2) lines that are parallel have the same alternate interior angles. Thus, the angle of inclination between the riser and tread is given by:
[tex]Tan x = \frac{rise}{tread} \\\\Tan x = \frac{7}{11} \\\\Tan x = 0.6364\\\\x=tan^{-1}0.6364[/tex]
x = 32.5°.
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