to find the distance between 2 points we use the following formula
![d=\sqrt[]{(x2-x1)^2+(y2-y1)^2}](https://img.qammunity.org/2023/formulas/mathematics/college/1h551ypq5weta3sw0dynfch7nxiwrgmnba.png)
according ti the image point 1 will be (0,0) and point b will be (4,3)
replace this points inti the formula
![\begin{gathered} d=\sqrt[]{(4-0)^2+(3-0)^2} \\ d=\sqrt[]{4^2+3^2} \\ d=\sqrt[]{16+9} \\ d=\sqrt[]{25} \\ d=5 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/wsh6c8b4ukelh2bzjsq7r2mkhkrl36e9ww.png)
this can be proved by drawing a right triangle using the 2 points like this
using the pithagorean the distance of the 2 points is the hypotenuse which leaves 5 as the distance.