Answer:
The rungs are perpendicular to the other side.
Explanation:
Given
The sides of ladder are parallel.Rungs is perpendicular to one side of the ladder.
Let
![a\parallel b](https://img.qammunity.org/2019/formulas/mathematics/high-school/ta78i707fd6bs19els74a0l90v725h1ofc.png)
![a\perp c](https://img.qammunity.org/2019/formulas/mathematics/high-school/fo8rf7i9rchvg91te3e8zdb1x4b1q5nbkk.png)
When two lines are parallel then the slopes of two lines are equal.
We can say
![m_1=m_2](https://img.qammunity.org/2019/formulas/mathematics/college/1vgn4ocrjzq7tzizbmhgs14es0g4g0d90p.png)
Where
= slope of line a( side of ladder)
= solpe of line b( side of ladder)
When two lines are perpendicular then slopes of two lines are opposite reciprocal to each other.
We can say
![m_2=-(1)/(m_3)](https://img.qammunity.org/2019/formulas/mathematics/high-school/29qt5t6fbil0120c7n52giufwh0614rsy3.png)
Where
= Slope of line b
=Slope of line c (rung)
By transitive property of equality we get
![m_1=-(1)/(m_3)](https://img.qammunity.org/2019/formulas/mathematics/high-school/8cjor6vggma5mbmomohvtahnge2zxm2p55.png)
Hence, the slope of side of ladder a and rung c are opposite reciprocal to each other.Therefore , the rungs are perpendicular to the other side.