Question

the midpoint m of $overline{st}$ has coordinates (-2, 2.5). point t has coordinates (14, -1). find the coordinates of point s. write the coordinates as decimals or integers. s = ( )

Explanation:

Step1: Recall mid - point formula

The mid - point formula for two points $(x_1,y_1)$ and $(x_2,y_2)$ is $M=(\frac{x_1 + x_2}{2},\frac{y_1 + y_2}{2})$. Let the coordinates of point $S$ be $(x,y)$ and point $T(14,-1)$ and mid - point $M(-2,2.5)$.

Step2: Solve for x - coordinate of S

We have $\frac{x + 14}{2}=-2$. Multiply both sides by 2: $x + 14=-4$. Then subtract 14 from both sides: $x=-4-14=-18$.

Step3: Solve for y - coordinate of S

We have $\frac{y+( - 1)}{2}=2.5$. Multiply both sides by 2: $y - 1 = 5$. Then add 1 to both sides: $y=5 + 1=6$.

Answer:

$(-18,6)$