Clue Detective
Solve two-unknown puzzles by combining clues: add or subtract equations and substitute one value into another. Free pre-algebra practice.
What you'll practice in Clue Detective
- Work with two unknowns across two clues
- Add or subtract equations to cancel a symbol
- Substitute a known value into another clue
- Reason from a small system of equations
Example. 🍎 + 🍌 = 9 and 🍎 − 🍌 = 3 — Add the clues: 2×🍎 = 12, so 🍎 = 6 and 🍌 = 3.
More algebra worlds to explore
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- Times Table Trail — Use times-table thinking to solve equations with repeated emojis — copies, factors, and coefficients like 3×🍎. Free algebra practice for kids.
- Order Ops Arcade — Practice order of operations and grouping: choose where the parentheses go and see how they change the result. Free algebra game for kids.
- Pattern Quest — Find the rule behind a growing pattern and predict what comes next. Free number-pattern and early-algebra practice for kids.
- Master Mix — Put it all together — a mixed review of equations, two-unknown clues, order of operations, and patterns. Free algebra practice for grades 4–5.