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								title: Create a Linear Scale with D3
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
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								# Create a Linear Scale with D3
 
							 
						 
					
						
							
								
									
										
										
										
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								## Problem Explanation
 
							 
						 
					
						
							
								
									
										
										
										
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								In this D3 challenge you are required to change the scale variable to create a linear scale. Then set the output variable to the scale called with an input argument of 50.
							 
						 
					
						
							
								
									
										
										
										
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								## Hints
 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								### Hint 1
 
							 
						 
					
						
							
								
									
										
										
										
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								The syntax for creating a scale is:
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```javascript
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								const scale = d3.scaleLinear();
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								### Hint 2
 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								The `const`  scale is a method, which accepts a value.
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								### Hint 3
 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								The scaling factor should be set to `50` .
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								### Hint 4
 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								The scaling factor is set like this:
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```javascript
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								const output = scale(scalingFactor);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								Where `scalingFactor`  is a number.
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								## Solutions
 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								< details > < summary > Solution 1 (Click to Show/Hide)< / summary > 
							 
						 
					
						
							
								
									
										
										
										
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								To solve this challenge, the `scale`  variable has to be re-initialized with a D3 scale ans the scaling factor in the output has to be set to `50` , to do this, change you code to look like this:
							 
						 
					
						
							
								
									
										
										
										
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								```html
							 
						 
					
						
							
								
									
										
										
										
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								< body > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  < script > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								    const scale = d3.scaleLinear();
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								    const output = scale(50);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								    d3.select("body")
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								      .append("h2")
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								      .text(output);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  < / script > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								< / body > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```
							 
						 
					
						
							
								
									
										
										
										
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								< / details >