D.
Determine if the relations’ graph forms a line.
Step-by-step explanation:
A function is a relation if the input values lead to only one output value.The input values, normally x values make up the domain, where as the output values form the domain.A function is a relation where the input values are associated with a single output.The vertical test is used to determine if a curve is a function.The line graph should only hit a single point on the curve.
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Relations and Functions :brainly.com/question/3296514
Keywords; relation, a function, vertical line test, output, input, maps
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A quadratic equation is one in which the highest exponent of x is 2.

is quadratic; the highest exponent is 2.
x³-3x²+1=0 is NOT quadratic. The highest exponent of x is 3, not 2.
5x-7=0 is NOT quadratic. The highest exponent of x is 1, not 2.
x²+3x-5=0 is quadratic; the highest exponent of x is 2.
x-5=9x+7 is NOT quadratic. The highest exponent of x is 1, not 2.
x²-x=3x+7 is quadratic; the highest exponent of x is 2.




Final answer: ⇒ 
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-Charlie
Yes; this is a linear function because you plug in a number and multiply it by two, so the function would be y=2x, which is linear despite the fact that it lacks a b value.
Hope this helps! :)