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Answer:
Needed length of board for ramp = 13 feet
will the board be long enough? = No, this board is not long enough
Step-by-step explanation:
Step 1: Draw an illustration representing the porch, the sidewalk, and the distance of the sidewalk to the base of the porch.
Step 2: use the Phytagorean Theorem:
[tex]a^{2} +b^{2} =c^{2}[/tex]
Substitute
25 + 144 = [tex]c^{2}[/tex]
Add
25 + 144 = [tex]\sqrt{169}[/tex] or 13 feet
Conclusion
13 feet > [tex]12\frac{3}{4}[/tex]