3 years ago

If (8z − 9)(8z + 9) = az2 − b, what is the value of a?

Mathematics

1 answer:

ikadub [295]3 years ago

8 0

<h3>Answer: a = 64</h3>

Explanation:

We use the difference of squares rule to say

(m-n)(m+n) = m^2 - n^2

So in this particular case,

(8z-9)(8z+9) = (8z)^2-(9)^2 = 64z^2 - 81

We can see that the 64 matches with the 'a' of the expression az^2-81, which must mean a = 64

Side note: This means b = 81

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To find the graph of the quadratic function, we find it's zeros.

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Given a second order polynomial expressed by the following equation:

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This polynomial has roots $x_{1}, x_{2}$ such that $ax^{2} + bx + c = a(x - x_{1})*(x - x_{2})$ , given by the following formulas:

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