Question

Describe how the graph of y + 3 = 2sin(3x + 90) compares to the graph of y = sin(x)

Answer 1

I suppose that 90 in your first equation is 90°

90°=(pi/2) radians

y+3= 2sin(3x +90°)

y=2sin(3x +90°)-3

y=2sin(3x +90°)-3 Angle in degres

y= 2sin(3x +pi/2)-3 Angle in radians

In google type:
"function graphs on line"

When you see list of results click on:

rechneronline.de/function-graphs/

When this page be open in blue rectacangle type:

2sin(3x + pi/2)-3

In gray rectacangle type:

sin(x)

Then click option Draw

You will see both graphs

Answer 2

On:
rechneronline.de/function-graphs/

In Dispay properties type follow values:

Range x-axis from -6.28 to 6.28

Range y-axis from -5.5 to 1.5