Which tools were used by ancient mathematicians to make geometric constructions?

compasses and straightedges

protractors and metric rulers

compasses and protractors

protractors and straightedges

Compasses and straightedges.

Step-by-step explanation:

The tool used by the ancient "Greek" mathematician to make geometric construction was the compasses and straightedges.The compasses and straightedges can be used to combine to transfer the segment of the given length onto a line.This can be done by only the following two steps:Put point A and open it, till mark is visible on point B.Liftoff and put the point on C and mark it on point D till its visible.The compasses and straightedges are used to trace the part of the triangle.

Y=3x+1 so the first one

It would be 18 cm