# Advanced Math

posted by
**Jason** on
.

Can someone check these for me? Please?

Use half-angle identity to find the exact value of cos165 degrees.

(-1/2) sqrt(2+sqrt(3))

Write the equation 2x+3y-5=0 in normal form.

(-2sqrt(13)/13)x- (3sqrt(13)/13)y+ (5 sqrt (13)/13) = 0

Find the distance between the lines with equations 3x-y=9 and y=3x-4.

sqrt (10)/2