Answer:
![-(1)/(3)](https://img.qammunity.org/2023/formulas/mathematics/high-school/getquuff49cohne05n98hv73iv77n9lzv4.png)
Step-by-step explanation:
Here, we want to get the gradient of the line L3
The equation of a straight line can be expressed as:
![y\text{ = mx + b}](https://img.qammunity.org/2023/formulas/mathematics/college/yw2q0p6vyzh9spy336dumq3zdpb67k7euq.png)
where m is the gradient (slope) and b is the y-intercept (the y-value when x = 0)
Now,let us write the equation of the first line in the slope-intercept form
Mathematically, we have this as:
![\begin{gathered} 3x-y\text{ + 2 = 0} \\ y\text{ = 3x + 2} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/11ia9d7g5ofbcuvbi539zzt4qzzlsnfuvm.png)
The gradient of the first line is 3
Now,let us get the gradient of the second line L3
Mathematically, when two lines ae perpendicular, the product of their gradients (slopes) equal -1
Thus, we have it that:
![\begin{gathered} m_1\text{ }* m_2\text{ = -1} \\ 3\text{ }* m_2\text{ = -1} \\ m_2\text{ = -}(1)/(3) \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/m0nb79ikd2oz030tz1kzv4jea4c8dtiodl.png)