Compound equations combine multiple linear relationships. Formula: solve nested or sequential equations. Key approach: work from outermost to innermost. Example: solve 2(3x + 1) = 10 by expanding first, then isolating x. Shortcut methods: recognize patterns in coefficient sequences. Common traps: sign errors during expansion, improper distribution of negatives. Exam tips: simplify before solving, draw visual representations. Time-saving strategy: estimate answer range first. Application areas: business calculations, physics formulas. Verification: substitute back into original form. Always work systematically through each layer. Master the distributive property to avoid mistakes. Practice with decimal and fractional coefficients.