Final answer:
The layout tool used to layout lines at an angle is the Plain Protractors.
Step-by-step explanation:
The layout tool used to layout lines at an angle is the Plain Protractors. A protractor is a tool used to measure and draw angles. It consists of a semicircular shape with degrees marked along its edge. By placing the protractor on a line, we can read the angle and accurately draw lines at specific angles.
By aligning the ruler's edge with the desired angle and drawing along it, you can measure and draw lines at specific angles with a ruler with degree markings.