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
143 over 100 Would be an examaple of a mixed number would just fine.
y = x² - 4x + 8
4x + y = 12
4x + y = 12
4x + (x² - 4x + 8) = 12
x² + 4x - 4x + 8 = 12
x² + 8 = 12
- 8 - 8
x² = 4
x = ±2
4x + y = 12
4(2) + y = 12
8 + y = 12
- 8 - 8
y = 4
4x + y = 12
4(-2) + y = 12
-8 + y = 12
+ 8 + 8
y = 20
(x, y) = (2, 4) and (-2, 20)