1.8k views
2 votes
The coordinates of A are (0,4) and the x-coordinate of B is 5. What is the y-coordinate of B if AB=13?(Two answers are possible.)

*could you give an explanation, i don't understand it but i know the possible answers which are 16 or -8*

1 Answer

5 votes

\overline{AB}=√((x_B-x_A)^2+(y_B-y_A)^2)\\\\ 13=√((5-0)^2+(y_B-4)^2)\\ 13=√(25+y_B^2-8y_B+16)\\ 13=√(y_B^2-8y_B+41)\\ 169=y_B^2-8y_B+41\\ y_B^2-8y_B-128=0\\ y_B^2+8y_B-16y_B-128=0\\ y_B(y_B+8)-16(y_B+8)=0\\ (y_B-16)(y_B+8)=0\\ y_B=16 \vee y_B=-8
User Bean
by
8.4k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories