A^2 + b^2 + c^2 - ab - bc - ca = 0
a.a + b.b + c.c = a.b + b.c + c.a
equating term by term:-
a = b
b = c
c = a
Therefore a = b = c
Answer:
0.44444444 or 4/9
Step-by-step explanation:
Since we know the value of
, we can rewrite the equation replacing the variables.

Now solve. While solving, remember the order of operations.
or 
Answer:
15
Step-by-step explanation:
|-7-8| = |-15| = 15##
Answer:
(x, y) = (-0.6, 0.8) or (1, 4)
Step-by-step explanation:
Use the second equation to substitute for y in the first.
(x -1)² +((2x +2) -2)² = 4
x -2x +1 + 4x² = 4 . . . . . . . eliminate parentheses
5x² -2x -3 = 0 . . . . . . . . . . subtract 4, collect terms
Now we can rearrange the middle term to ease factoring by grouping.
(5x² -5x) +(3x -3) = 0
5x(x -1) +3(x -1) = 0
(5x +3)(x -1) = 0
The values of x that make these factors zero are ...
x = -3/5, x = 1
The corresponding values of y are ...
y = 2(-3/5)+2 = 4/5 . . . . for x = -3/5
y = 2(1) +2 = 4 . . . . . . . . for x = 1
The solutions are: (x, y) = (-3/5, 4/5) or (1, 4).
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A graphing calculator verifies these solutions.
Half of perimeter (or length+ width) is:
222 mm /2= 111 mm.
111 mm- 60 mm= 51 mm
The width of the rectangle is 51 mm~