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

Mar 14, 2019

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(8z − 9)(8z + 9) = az2 − b

First you must swich sides:

az * 2 - b = (8z - 9) (8z + 9)

az * 2 - b = (8z - 9) (8z + 9)

az * 2 - b + b = (8z - 9) (8z + 9) + b

Then symplify

az * 2 = (8z - 9) (8z + 9) + b

Then divide both sides by z * 2

$$\frac{az*2}{z * 2}$$ $$= \frac{(8z - 9)(8z + 9)}{z*2}+\frac{b}{z*2}$$

Then symplify

$$a = \frac{(8z-9)(8z+9)+b}{2z}$$

Hope this helps ;P

Mar 14, 2019