-3r+15≥4(r-2) please help me

  -3r + 15 ≥ 4(r - 2)
  -3r + 15 ≥ 4(r) - 4(2)
  -3r + 15 ≥ 4r - 8
+ 3r         + 3r
           15 ≥ 7r - 8
          + 8       + 8
           23 ≥ 7r
            7     7
          3²/₇ ≥ r
              r ≤ 3²/₇

Solution Set: x ∈ (-∞, 3²/₇]

−3r+15≥4r−8

 Subtract 4r from both sides.

−3r+15−4r≥4r−8−4r

−7r+15≥−8

 Subtract 15 from both sides.

−7r+15−15≥−8−15

−7r≥−23

Divide both sides by -7.

−7r/−7 ≥ −23/−7

r ≤ 23/7

You need to show the graph

Arhombus is a quadrilateral.