Consider the center of the nonagon. If we join the center to all the vertices, the central angle of 360°, is divided into 9 equal angles, each with a measure of:
360°/9=40°
So to a nonagon rotated 40°, clockwise or counterclockwise, is indistinguishable from the original one.
similarly if we rotate 80 ° c.wise or c.c.wise
in general, a nonagon has a rotational symmetry of 40°n,
where n∈{...-3, -2, -1, 0, 1, 2, 3}...
where 40°n, for n negative, means we are rotating clockwise.
Answer: any angle which is a multiple of 40°
Answer:
(a) (5, -3)
Step-by-step explanation:
The "substitution method" for solving a system of equations requires that you write an expression that can be substituted for a variable in one or more of the other equations in the system.
<h3>Expression to substitute</h3>
The given equations are ...
We notice the first equation gives an expression for y. This is exactly what we want to substitute for y in the second equation.
<h3>Substitution</h3>
When the expression (x-8) is substituted for y in the second equation, you get ...
2x +3(x -8) = 1
This simplifies to ...
5x -24 = 1
<h3>Solution</h3>
This 2-step equation can now be solved in the usual way:
5x = 25 . . . . . . add 24 to isolate the variable term
x = 25/5 = 5 . . . . . divide by the coefficient of x
Note that we now know what the correct answer choice is.
Using the expression for y, we find ...
y = x -8 = 5 -8 = -3
The solution is (x, y) = (5, -3).
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The attached graph confirms this solution.
Step-by-step explanation:
-2x(x2 - 3)
-2x³+6x
Hope it helps ☺️