Question

(3,4-5)+(4,4-7)+(5,4-9)+(6,4+11)+(7,4-13)=

Answer 1

(3,4-5)+(4,4-7)+(5,4-9)+(6,4+11)+(7,4-13)=-1,6+(-2,6)+(-3,6)+17,4+(-5,6)=4