distance from (0,0) to (3,4)
The distance is the norm of the difference of the points: the square root of the sum of the squared coordinate differences
Let's calculate: ‖(3, 4) -(0, 0)‖
ⅰ (3, 4) -(0, 0) = (3, 4)
‖(3, 4)‖
ⅰ ‖(3, 4)‖ = 32 + 42
32 + 42
ⓘ Powers are computed before multiplications, additions and subtractions. An integer power is a repeated product: 32 = 3×3 = 9, 42 = 4×4 = 16
9 + 16
ⓘ Parentheses are computed first: 9 + 16 = 25
25
ⓘ The square root of a number is the positive number whose square is that number: 25 = 5; 52 = 25
▶Distance:   5