Question

Reperul cartezian xoy se consideră punctele A(1,1) B(4,1) C(4,4). Aratati ca AB=BC

Answer 1

AB= $\sqrt{ (x(A)-x(B))^{2}+(y(A)-y(B))^{2} }= \sqrt{ (1-4)^{2}+ (1-1)^{2} } = \sqrt{9+0} =$=√9=3 cm

BC=$\sqrt{ (x(B)-x(C))^{2}+(y(B)-y(C))^{2} }= \sqrt{ (4-4)^{2}+ (1-4)^{2} } = \sqrt{0+9}$=√9=3 cm

⇒ AB=BC = 3 cm