Question

The midpoint of has coordinates of (4, -9). The endpoint A has coordinates (-3, -5). What are the coordinates of B?

Answer 1

9514 1404 393

Answer:

  (11, -13)

Step-by-step explanation:

If midpoint M is halfway between A and B:

  M = (A +B)/2

Then B is ...

  B = 2M -A

  B = 2(4, -9) -(-3, -5) = (8+3, -18+5)

  B = (11, -13)

Answer 2

Answer:

Use the midpoint formula:

$midpoint=(\frac{x_{1}+x_{2}}{2}, \frac{y_{1}+y_{2}}{2})$

• Endpoint A = (x₁, y₁) = (-3, -5)
• Endpoint B = (x₂, y₂)
• Midpoint = (4, -9)

Substitute in the values:

$(4, -9)=(\frac{-3+x_{2}}{2} +\frac{-5+y_{2}}{2} )$

$4=\frac{-3+x_{2}}{2} \\4(2)=-3+x_{2}\\8+3=x_{2}\\x_{2}=11$      $-9=\frac{-5+y_{2}}{2} \\(-9)(2)=-5+y_{2}\\-18+5=y_{2}\\y_{2}=-13$

Therefore, Point B = (11, -13)