How do I calculate this parent function of a linear function? The parent function of a linear function is y=x. When the parent function is changed to y=x+5, how does the graph transform?

Could somebody me with this radical simplification?

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

What is the effect on the graph of the function f(x) = x2 when f(x) is changed to f(x) − 4?