Complete the square to rewrite y=x^2+8x-4 in vertex form, and then identify the minimum y-value of the function. a. the minimum value is –20. b. the minimum value is –2. c. the minimum value is –4. d. the minimum value is –16.

The graph shows the decibel measure for sounds depending on how many times as intense they are as the threshold of sound. noise in a quiet room is 500 times as intense as the threshold of sound. what is the decibel measurement for the quiet room? 20 decibels28 decibels200 decibels280 decibels