Longer wavelength means lower frequency (lower pitch)
The percent discount is 30%.
If you multiply $32 by .30, you will get $9.60. That is the amount of the discount. If you subtract $9.60 from $32, you will get $22.40 which is what he paid before tax. Therefore the percent discount is 30%.
Answer:
<em>p = ± q / 5r + 8; Option D</em>
Step-by-step explanation:
We are given the following equation; q^2 / p^2 - 16p + 64 = 25r^2;
q^2 / p^2 - 16p + 64 = 25r^2 ⇒ Let us factor p^2 - 16p + 64, as such,
p^2 - 16p + 64,
( p )^2 - 2 * ( p ) * ( 8 ) + ( 8 )^2,
( p - 8 )^2 ⇒ Now let us substitute this into the equation q^2 / p^2 - 16p + 64 = 25r^2 in replacement of p^2 - 16p + 64,
q^2 / ( p - 8 )^2 = 25r^2 ⇒ multiply either side by ( p - 8 )^2,
q^2 = 25r^2 * ( ( p - 8 )^2 ) ⇒ divide either side by 25r^2,
q^2 / 25r^2 = ( p - 8 )^2 ⇒ Now apply square root on either side,
| p - 8 | = √( q^2 / 25r^2 ) ⇒ Simplify,
| p - 8 | = q / 5r,
| p | = q / 5r + 8,
<em>Answer; p = ± q / 5r + 8; Option D</em>
