Step by step
The question
Question: shade the points that are less than 2 cm from A and nearer to A than to B, with A B = 3 cm.
Less than, and nearer: the edges themselves are not included.
So we draw them dashed.
1 Read the rules
A and B are 3 cm apart.
Two rules: near A, and nearer to A than to B.
2 Less than 2 cm from A
Points 2 cm from A make a circle.
Less than 2 cm: inside it.
Dashed, because the circle itself is not included.
3 Nearer to A than to B
Points the same distance from A and B are on the perpendicular bisector of A B.
Nearer to A: on A's side of it.
Careful!
The region must follow both rules.
Only the part that is inside the circle and on A's side.
4 Shade the region
Shade the part inside the circle, on A's side of the line.
5 Check
Let's check one point in the shaded part: it is 1 cm from A, less than 2 cm, and 4 cm from B, so nearer to A.
So it is right!
Let's look back.
First: read the rules.
Then: less than 2 cm from A.
Then: nearer to A than to B.
Then: shade the region.
Last: check.