Answer:
QR = 5 units
Explanation:
The formula for calculating midpoint is expressed as;
R(X, Y) = {(x2+x1)/2, (y2+y1)/2}
X = x1+x2/2
Y = y1+y2/2
Given the follwing coordinates
Q (-3,7) and P (3, -1),
Get the midpoint R
R (X, Y) = (-3+3/2, 7-1/2)
R (X, Y) = (0/2, 6/2)
R (X, Y) = (0, 3)
Hence the midpoint R is (0,3)
Get the length of QR using the formula for calculating the distance between two points
[tex]QR\text{ = }\sqrt[]{(x_2-x_1)^2+(y_2-y_1)^2}[/tex]Given the coordinates Q(-3, 7) and R(0,3)
[tex]\begin{gathered} QR\text{ = }\sqrt[]{(0-(-3))^2+(3-7)^2} \\ QR\text{ = }\sqrt[]{3^2+(-4)^2} \\ QR\text{ = }\sqrt[]{9+16} \\ QR\text{ = }\sqrt[]{25} \\ QR\text{ = 5} \end{gathered}[/tex]Hence the length of QR is 5 units