Distance between (x₁, y₁) and (x₂, y₂) is the square root of (x₂ − x₁)² + (y₂ − y₁)². That is the Pythagorean theorem on a coordinate plane. Midpoint and distance as a pair are in midpoint and distance.
Draw the right triangle
Subtract the x-coordinates to get one leg. Subtract the y-coordinates to get the other. Square, add, square-root. You can skip the frozen formula and still get the same number from a² + b² = c². Horizontal or vertical segments are just the absolute difference of one coordinate.
Pythagorean setup is in Pythagorean theorem and special right triangles. Slope uses the same two points but divides instead of squaring, in slope. Formulas as a set are in ACT Math formulas.
The bottom line
Legs from the coordinate gaps. Hypotenuse is the distance.
Start practicing
Start with a free diagnostic, then drill your weak spots with 15-question quizzes and track how you're doing across Reading, English, and Math. Compare plans whenever you're ready to go further.
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