Equations as Balance Scales (series)
A series of balance-scale cartoons explaining the equals sign, equations, inequalities, symmetry of equality, and solving 2x + 11 = 25 step by step.
Use this cartoon
Free for classrooms, worksheets, slides and other non-commercial use under CC BY-NC 4.0, with credit to Ben Orlin.
Cartoon by Ben Orlin, Math with Bad Drawings. https://cartoons.mathwithbaddrawings.com/2014-01-01-equations-as-balance-scales/ (CC BY-NC 4.0)Transcript
[1] "4 + 5 = __ + 3" Student: "The blank has to be 9, right? Because 4 + 5 = 9 and I stop paying attention after that."
[2] "x = 20" x (on a balance scale, opposite gold bars): "Gadzooks! I weigh that much?"
[3] "x + 15 = 35" x (with three bars, opposite seven bars marked "5 each"): "We balance!"
[4] "A > B" A (heavy side): "Yes! I've always wanted to be The Greater!"
[5] "A < B" A (light side): "Aww. I'm lesser now."
[6] Two creatures with "=" between them: "We're equal!" Swapped: "Still equal!"
[7] "2x + 11 = 25": three balance scales showing the equation simplified step by step: remove 11 from both sides, then halve, leaving x = 7.