Question

Express root 4.2 on Number line with steps

Answer 1

hope this will help you.
BE= BD= √4.2

Answer 2

To express 4.2 on number line steps:

The following is the method to measure root 4.2,

Consider a line segment AB on number line where AB=4.2, take a point C next to B such that BC = 1 unit.

Consider midpoint of AC as center O. Now with radius OC draw a semi-circle. Draw a straight line from B onto the semicircle to cut it at D. BD will be the root of AB.

The following attached image shows the same.

B D=$\sqrt{4.2}$