Connect the dots on the coordinate grid to uncover the hidden image.

To solve this problem, we need to plot the points on the grid and connect them in the order given for each line. Let's break it down step by step.

Step 1: Understand the Grid
The grid has an x-axis (horizontal) numbered 1 to 20 and a y-axis (vertical) numbered 1 to 20. Each point is given as `(x, y)`, where `x` is the horizontal position and `y` is the vertical position.

Step 2: Plot Line 1
Points: `(9,11), (6,12), (5,13)`
- Start at x=9, y=11.
- Move to x=6, y=12.
- Move to x=5, y=13.
This creates a short diagonal line segment going up and to the left. This looks like the tip of a finger or a small part of a shape.

Step 3: Plot Line 2
Points: `(15,7), (13,6), (11,6), (12,11)`
- Start at x=15, y=7.
- Move to x=13, y=6.
- Move to x=11, y=6.
- Move to x=12, y=11.
This creates a shape that goes down slightly, then left, then sharply up. This looks like another finger or part of a hand.

Step 4: Plot Line 3
Points: `(8,13), (9,14), (10,16)`
- Start at x=8, y=13.
- Move to x=9, y=14.
- Move to x=10, y=16.
This is another short diagonal line going up and to the right.

Step 5: Plot Line 4
This is the longest and most complex line. Let's trace it carefully.
Points: `(7,15), (8,17), (6,17), (9,11), (10,7), (10,4), (11,4), (13,3), (14,3), (15,16,6), (17,8), (14,8), (16,11), (16,12), (15,12), (16,15), (14,17), (13,15), (12,15), (11,12), (11,16), (10,18), (9,16)`

Wait, there seems to be a typo in the provided text for Line 4: `(15,16,6)`. Looking at the sequence, it likely means `(15,6)` or `(16,6)`. Let's look at the surrounding points: `(14,3), (15,?,6), (17,8)`. It's probably `(15,6)` or `(16,6)`. Given the pattern of drawing a hand, let's assume it's `(15,6)` or similar to form the palm/base. Actually, looking closely at the image text, it says `(15,16,6)`. This is almost certainly a typo for `(15,6)` or `(16,6)`. Let's re-read the sequence:
`(14,3), (15,6), (17,8)...` makes sense for a thumb base. Or perhaps `(16,6)`. Let's assume `(15,6)` for now as it fits between 14 and 17 on the x-axis.

Let's re-examine the whole shape formed by all lines together.
- Line 1: Tip of a finger (pinkie?)
- Line 3: Tip of another finger (index?)
- Line 2: Middle/ring finger area?
- Line 4: This long line connects everything. It starts high at `(7,15)`, goes up to `(8,17)`, over to `(6,17)`, then drops down through `(9,11)`... wait, `(9,11)` was the start of Line 1. So Line 4 connects to Line 1.
Then it goes down to `(10,7)`, `(10,4)`, `(11,4)`... this forms the bottom/wrist area.
Then up to `(13,3), (14,3)`... thumb base?
Then up to `(15,6)` [assuming typo], `(17,8)`... thumb tip?
Then back across `(14,8), (16,11)...` this part is tricky.

Let's look at the overall picture these coordinates create.
The points cluster in a way that suggests a hand.
- The top points `(8,17), (10,16), (9,16), (10,18)` are the fingertips.
- The middle points `(9,11), (12,11), (11,12)` are the knuckles.
- The bottom points `(10,4), (11,4), (13,3), (14,3)` are the wrist/palm base.
- The side points `(15,6), (17,8)` form the thumb.

Specifically:
- Line 1 `(9,11)-(6,12)-(5,13)` is the pinky finger.
- Line 3 `(8,13)-(9,14)-(10,16)` is the index/middle finger area.
- Line 2 `(15,7)-(13,6)-(11,6)-(12,11)` is the ring/middle finger area.
- Line 4 traces the outline: starting from the pinky side, going around the fingertips, down the index side, across the thumb, and along the palm/wrist.

When you connect all these dots, the hidden picture is a hand (specifically, an open hand with fingers spread).

Final Answer:
The hidden picture is a hand.