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逐步求解任何几何题。按形状选择、在图形中求 x、证明三角形全等、计算体积——70+ 工具 + 可读图片的 AI 求解器。

Need to solve a geometry problem? Start with the shape or topic. Each entry below opens a dedicated solver that walks through the formula, plugs in your values, and shows every step. For unusual problems (composite figures, handwritten work, photos of textbook pages), jump straight to the AI Geometry Solver.

Solve by Topic

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三角形求解器

SSS, SAS, ASA, AAS — all sides, angles, area, perimeter
∠

Find x in Triangle

Solve for unknown angle or side using angle sum / Pythagoras
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Quadrilateral Solver

Square, rectangle, rhombus, trapezoid — auto-classify
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Circle Solver

Radius, diameter, area, circumference, sectors, arcs
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Polygon Solver

Interior/exterior angles, area, sides for any n-gon
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坐标几何

Distance, midpoint, slope, section formula
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AI Geometry Solver

Upload a photo or describe in plain English
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Composite Figure Solver

L-shapes, donuts, compound 2D and 3D figures
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Proof Solver

Two-column proofs: congruence, similarity, parallel lines
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3D Volume / Surface Area

Cube, prism, sphere, cylinder, cone, pyramid

How to Solve a Geometry Problem

  1. Identify the shape. Triangle? Quadrilateral? Circle? 3D solid? — pick the corresponding solver from the grid above.
  2. List what you know. Sides, angles, area, perimeter, coordinates — every solver shows which input combinations it accepts.
  3. Pick the right formula. Each tool auto-selects: SSS triangles use Heron, missing-angle triangles use the angle sum, similar triangles use ratios.
  4. Read every step. Solvers show substitutions, intermediate values, and the final answer with units — copy them into your homework.
  5. Stuck on a weird shape? Use the AI Geometry Solver — paste a photo and let the model figure out which formula applies.

Worked Example: Find x in a Geometry Problem

Problem: A triangle has angles 50°, 65°, and x. Find x.

  1. Apply the triangle angle sum: ∠₁ + ∠₂ + ∠₃ = 180°
  2. Substitute: 50° + 65° + x = 180°
  3. Simplify: 115° + x = 180°
  4. Solve: x = 65°

This is exactly how the triangle solver works under the hood — except it handles SSS / SAS / ASA / Law of Cosines / Law of Sines variants automatically.

Geometry Solver FAQ

How do I find x in a geometry problem?

Identify what x represents (angle, side length, area), find the geometric relationship that involves x and the known values (angle sum, Pythagorean theorem, similar triangles ratio, area formula), write the equation, and solve algebraically. Each solver in the grid above does this automatically for its specific shape.

Which solver should I use for a triangle with 3 known sides?

Use the Heron's formula calculator for area, or the general triangle solver for sides+angles+area all at once. Both accept 3-side input (SSS) and return the rest.

Can I solve composite figure problems?

Yes — the composite figure calculator decomposes L-shapes, donuts, stadiums and other compound shapes into rectangles / triangles / circles, sums the parts, and returns the total area or volume.

Is there a solver for two-column proofs?

Yes — the geometric proofs calculator generates two-column proofs for triangle congruence (SSS, SAS, ASA, AAS, HL), similar triangles (AA, SAS, SSS), and parallel-line angle theorems.

What if my problem doesn't fit any of these categories?

Use the AI Geometry Solver — upload a photo or describe the problem in plain English, and the AI picks the right approach.