Define a variable and write an expression for the phrase. 6 minus a number

Both the red and blue line segments stretch from the center of the circle to a point on the circle. the length of the blue segment is 5. how long is the red line segment?

Bernice paid $162 in interest on a loan of $1800 borrowed at 6%. how long did it take her to pay the loan off?

Use the method of cylindrical shells to find the volume v generated by rotating the region bounded by the curves about the given axis. y = 7ex, y = 7e^-x, x = 1; about the y-axis