4a =
x=80+2y
x+3
6-1/x-1/x find the domain
0/0.5
arcsen = $\sqrt{94/100}$
5 over 2x - 2 over x
6-1/x+1/x find the domain
2x+3y=420
3x+6y=220
$x^{2}$+2 $x$=17