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A balanced and proportionate likeness observed in two sides of an item is characterized as symmetry. The shape can be completed as shown below.
<h3>What is symmetry?</h3>
A balanced and proportionate likeness observed in two sides of an item is characterized as symmetry. It signifies that one side is a mirror image of the other. The line of symmetry is the imaginary line or axis along which you can fold a figure to produce the symmetrical halves.
The shape can be completed as shown below, so that the complete shape is symmetrical about the given axis.
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Y=-9x because y=mx+b is the formula so plug in the slope, m(-9) and the x-intercept, x(0)