dolphin
Get Started

SAT Math skill page

SAT Geometry Practice

Review the SAT geometry moves that turn diagrams into equations and formulas into points.

Practice geometry in Dolphin Try examples
12-18 min practice time 3 examples on page Geometry and Trigonometry
Practice time 12-18 min
On-page examples 3 examples
Best for Geometry and Trigonometry

What this tests

What to know for this SAT skill

Practice examples

Try a few SAT-style questions

Example 1 Easy

A triangle has angle measures 50 degrees, 60 degrees, and x degrees. What is x?

  1. 60
  2. 70
  3. 80
  4. 90
Show answer and explanation

Answer: 70

Triangle angles add to 180 degrees. So x = 180 - 50 - 60 = 70.

Example 2 Medium

A rectangle has length 10 and perimeter 34. What is its width?

  1. 5
  2. 7
  3. 12
  4. 14
Show answer and explanation

Answer: 7

Perimeter is 2(length + width). So 34 = 2(10 + w), which gives 17 = 10 + w and w = 7.

Example 3 Hard

A circle has circumference 18pi. What is its area?

  1. 18pi
  2. 36pi
  3. 81pi
  4. 324pi
Show answer and explanation

Answer: 81pi

Circumference is 2pi r. If 2pi r = 18pi, then r = 9. The area is pi r^2 = 81pi.

Avoid these traps

Common mistakes on this skill

Using the wrong formula

Circle circumference and area both use pi, but circumference is 2pi r and area is pi r squared.

Forgetting angle totals

Triangles add to 180 degrees, straight lines add to 180 degrees, and full circles add to 360 degrees.

Mixing up radius and diameter

The diameter is twice the radius. Check which one the question gives before using a circle formula.

Study plan

How to practice this skill in Dolphin

  1. Memorize the high-frequency SAT geometry formulas.
  2. Label diagrams with every given and inferred value.
  3. Write a short equation before trying answer choices.
  4. Check units: length, square units, and cubic units are not interchangeable.
Practice geometry in Dolphin

Related practice

Build the surrounding skills

SAT Right Triangles PracticeSAT Ratios and Proportions PracticeSAT Quadratic Equations PracticeSAT Math skill hub

Skill cluster

Keep practicing SAT Math

SAT Math skill hub SAT Linear Equations PracticeSAT Systems of Equations PracticeSAT Linear Functions PracticeSAT Quadratic Equations PracticeSAT Percentages PracticeSAT Ratios and Proportions PracticeSAT Probability PracticeSAT Right Triangles PracticeSAT Data Analysis PracticeSAT Circle Equations Practice SAT Reading and Writing Practice Pages Dolphin SAT study guides SAT score guides by college

FAQ

Questions about SAT Geometry Practice

How much geometry is on SAT Math?

Geometry is a smaller but important part of SAT Math. It often appears through triangles, circles, angles, and area.

Are formulas provided on the SAT?

Some formulas are provided, but you still need to know when and how to use them quickly.

What is the best way to study SAT geometry?

Practice recognizing the formula or relationship a diagram is asking for before doing calculations.