Answer: 25x² - 64
<u>Step-by-step explanation:</u>
(5x + 8)(5x - 8)
= 5x(5x - 8) + 8(5x - 8)
= 25x² - 40x + 40x - 64
= 25x² + 0x - 64
= 
NOTE: descending powers means the biggest exponent goes first, then the next biggest exponent, etc.
For example: x⁴ then x³ then x² then x then the number (which is actually x⁰)
The 68 - 95 - 99.7 rule, gives the basis to solve this question.
It says that for a normal distribution 95% of the results are between the mean minus 2 standard deviations and the mean plus 2 standard deviations.
Here:
mean = 64.5 inches,
standard deviaton = 2.5 inches
mean - 2 standard deviations = 64.5 inches - 5 inches = 59.5 inches
mean + 2 standard deviations = 64.5 inches + 5 inches = 69.5 inches
Then, the answer is that 95% of women range approximately between 59.5 inches and 69.5 inches.
7(x^2 +5x-7)
i think this is how it works
root 30 ..................