Question #07bcc

1 Answer
Feb 17, 2017

Substitute rcos(theta)" for "x and rsin(theta)" for "y, then write r as a function of theta.

Explanation:

Substitute rcos(theta)" for "x and rsin(theta)" for "y:

5rcos(theta) - 4rsin(theta) = -7

Remove the common factor r:

r(5cos(theta) - 4sin(theta)) = -7

Divide both sides by 5cos(theta)-4sin(theta):

r = (-7)/(5cos(theta) - 4sin(theta))

Multiply numerator and denominator by -1:

r = 7/(4sin(theta)-5cos(theta))