To solve this probem you must apply the proccedure shown below:
1. You have the original photo was [tex]800 pixels
[/tex]wide and the new photo will be [tex]1260 pixels
[/tex] wide. Therefore, the factor is:
[tex]F=1206/800 \\ F=1.575[/tex]
2. Now, you can calculate the height of the new photo by multiplying the factor by the original height:
[tex]h=(600 pixels)(1.575) \\ h=945 pixels[/tex]
Therefore, the answer is: [tex]945 pixels[/tex]