-15 i think if not u just got to use the quadratic formula.
Let
The origin of coordinates the tree
r1 = vector position of the child 1.
r2 = vector position of the child 2
Child 1:
r1 = (12i + 12j)
Child 2:
r2 = (-18i + 11j)
The scalar product will be given by:
r1.r2 = ((12) * (- 18)) + ((12) * (11)) = - 84
The scalar product of their net displacements from the tree is -84m ^ 2
Given:
The point is (-12,-8).
Rule of transformation is 
.
To find:
The coordinates of image after transformation.
Solution:
According to the rule of transformation , first the point is dilated by factor 
with origin as center of dilation after that it was rotated 270 degrees anticlockwise.
If a point is dilated by factor with origin as center of dilation, then
If a point is rotated 270 degrees anticlockwise, then
Therefore, the coordinates of image after transformation are (-2,3).
You would have to move terms which will bring you to 14.4 x - 19.2 = 19.2 - 4.8x the you would combine like terms then you would get 19.2x= 38.4 then you divide both sides by 19.2 and get 2 as your answer.
You can choose the coordinates of any two points on the vertical line where x=5.
So for the coordinates, you need a y value for both. Since the points have to be on that line, you already know that the x value has to be 5.
