Question

solve for r.
$18r - 10r - 20r + 2r + 9r = 18$
$r = \square$

Explanation:

Step1: Combine like terms

$18r - 10r - 20r + 2r + 9r = (18-10-20+2+9)r = -1r$

Step2: Isolate the variable r

$-r = 18 \implies r = -18$

Answer:

$r = -18$