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He line of symmetry for the quadratic equation y = ax 2 - 8x - 3 is x = 2. What is the value of "a"?

A. -2
B. -1
C. 2

1 Answer

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Answer:

C. 2

Explanation:

When the coefficients of the standard-form quadratic are a, b, and c, the equation of the line of symmetry is ...

x = -b/(2a)

Solving for 'a', we find ...

a = -b/(2x)

For the given values b=-8 and x=2, the value of 'a' is ...

a = -(-8)/(2ยท2) = 8/4 = 2

The value of "a" is 2.

He line of symmetry for the quadratic equation y = ax 2 - 8x - 3 is x = 2. What is-example-1