The McDonald's logo is a perfect example of parabolas appearing in life. If they were to be expressed in equations, we know that they would be negative parabolas, and that "a" would be greater than 1 because of how stretched it is. However, the arch has many sizes, depending on the popularity of the location.
Many people have resulted with different equations and solutions for the Golden Arches. For example, the standard form is y = - x2 + 8x - 11 and the vertex form is y = -(x - 4)2 + 5, but this is only the equations one person came up with. In other words, the Golden Arches representing McDonald’s has various answers, so we don’t definitely know which answer is correct yet.
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