81.4k views
2 votes
A builder makes staircases where each step is 29 cm long and rises 18 cm so people dont trip. Every staircase has a stringer - a diagonal support connecting all the steps. What is the length of the stringer of the staircase?

User Xiaochen
by
5.3k points

2 Answers

5 votes

Answer:

the number you want is 28 not 29. the answer is 199.7, look at the picture for proof.

Explanation:

A builder makes staircases where each step is 29 cm long and rises 18 cm so people-example-1
User Maligree
by
4.9k points
4 votes

Let x represent length of the stringer of the staircase.

We have been given that a builder makes staircases where each step is 29 cm long and rises 18 cm so people don't trip. Every staircase has a stringer - a diagonal support connecting all the steps. We are asked to find the length of the stringer of the staircase.

The length of the stringer of the staircase will be equal to diagonal of right triangle with two legs 29 cm and 18 cm.

Using Pythagoras theorem, we will get:


x^2=29^2+18^2


x^2=841+324


x^2=1165

Now we will take square root of both sides of equation.


√(x^2)=\pm√(1165)


x=\pm 34.13209


x\approx \pm 34.13

Since length cannot be negative, therefore, the length of the stringer of the staircase would be approximately 34.13 cm.

User Mkoryak
by
4.4k points