Pythagorean theoremThe rule that in a right triangle, the squares of the two shorter sides add up to the square of the longest side: a² + b² = c².
You’ll leave with these skills
01Find the distance between two points on a graphSubtract the x-values and the y-values to get the two legs of a right triangle, then square them, add, and take the square root.
02Find the midpoint of a segmentAverage the two x-values and the two y-values to get the midpoint’s coordinates.
03Find a segment’s length from its midpoint and one endpointFind the missing endpoint by repeating the step from the known endpoint to the midpoint, then find the distance between the two endpoints.
04Match a distance to square-root answer choices in DesmosType the distance formula with the two points into Desmos, type each square-root answer choice on its own line, and pick the one with the same decimal.
This lesson is part of the full library
202 lessons that teach every skill the SAT tests
66Math
40Reading
24Grammar
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