The answer is

In the choices; the coefficients 21, 32 and 10 are not perfect squares.
Answer:
(x,y) => (x+3, y+4)
Step-by-step explanation:
Given a triangle DEF, D(4,2), E(3,3), F(2,1).
Centroid of the area (and the vertices) equals the mean of the coordinates, namely ( (4+3+2)/3, (2+3+1)/3 ) = (3,2)
To translate (3,2) to (6,6), we need the rule
(x,y) => x+(6-3), y+(6-2), or
(x,y) => (x+3, y+4)
(x+y)^2=x^2+y^2+2xy=73+2*24=73+48=121
⇒ (x+y)^2=121
Answer:
y=2x-23
Step-by-step explanation:
m=(-9+7)/(7-8)=-2/-1=2
y=2x+b
-7=2(8)+b
-7-16=b
b=-23
y=2x-23