The given vectors form a right angled triangle. This means that we can apply Pythagorean theorem which states that:
(hypotenuse)^2 = (side1)^2 + (side2)^2
We are given that:
hypotenuse = 75 cm
side1 = 21 cm
side2 = x cm
Substitute with the gives in the equation to get the value of x as follows:
(75)^2 = (21)^2 + (x)^2
x^2 = 5184
x = 72 cm
