| 49 | The lowest point | Medium | Lemma | Completing the square | |
| 1206 | Quadratic Equation with Binomial Roots | Medium | Hall & Knight | Quadratic equationsRoots | |
| 1209 | Quadratic Equation with Parametric Surd Roots | Medium | Hall & Knight | Quadratic equationsParameters+1 | |
| 1212 | Quadratic from Pure Imaginary Roots | Medium | Hall & Knight | Quadratic equationsPure imaginary roots+1 | |
| 1217 | Equal roots parameter values 2 | Medium | Hall & Knight | discriminantequal roots | |
| 1218 | Roots equal in magnitude and opposite in sign | Medium | Hall & Knight | roots of quadraticssum of roots | |
| 1220 | Symmetric function of roots 4 | Medium | Hall & Knight | roots of quadratic equationVieta's formulas+1 | |
| 1221 | Difference of roots squared ratio | Medium | Hall & Knight | roots of quadratic equationVieta's formulas | |
| 1225 | Form equation with derived roots | Medium | Hall & Knight | quadratic equationssum and product of roots | |
| 1227 | Condition for multiple roots | Medium | Hall & Knight | roots of a quadraticVieta's formulas | |
| 1228 | Form equation with modified roots | Medium | Hall & Knight | quadratic equationsVieta's formulas+1 | |
| 1229 | Equation from sum and difference squares | Medium | Hall & Knight | quadratic equationssum and difference of roots | |
| 1230 | Signs of quadratic roots | Medium | Hall & Knight | quadratic equationsDescartes' rule of signs+1 | |
| 1231 | Limits for real roots | Medium | Hall & Knight | quadratic equationsdiscriminant+1 | |
| 1232 | Bounds of a rational fraction | Medium | Hall & Knight | rational functionsdiscriminant+1 | |
| 1233 | Bounds of a symmetric fraction | Medium | Hall & Knight | rational functionsdiscriminant+1 | |
| 1234 | Excluded values of a fraction | Medium | Hall & Knight | rational functionsdiscriminant+1 | |
| 1235 | Equation from modified roots | Medium | Hall & Knight | roots of equationssum and product of roots+1 | |
| 1236 | Ratio of roots identity | Medium | Hall & Knight | Quadratic equationsRoots and coefficients | |
| 1237 | Range of a rational expression | Medium | Hall & Knight | Range of rational functionsDiscriminant method | |
| 1238 | Difference of roots invariance | Medium | Hall & Knight | DiscriminantRoots of quadratic equations | |
| 1239 | Parameter bounds for real values | Medium | Hall & Knight | Range of rational functionsDiscriminant method | |
| 1240 | Maximum value of a fraction | Medium | Hall & Knight | ExtremaDiscriminant method | |
| 1241 | Excluded values of a rational expression | Medium | Hall & Knight | Range of rational functionsDiscriminant method | |
| 1242 | Condition for Impossible Roots | Medium | Hall & Knight | quadratic equationsdiscriminant+1 | |
| 1244 | Resolution into rational factors | Medium | Hall & Knight | quadratic equationsdiscriminant+1 | |
| 1245 | Linear factors of quadratic in two variables | Medium | Hall & Knight | quadratic equationsdiscriminant+1 | |
| 1246 | Real linear factors | Medium | Hall & Knight | quadratic equationsdiscriminant+1 | |
| 1247 | Common root of two quadratics | Medium | Hall & Knight | quadratic equationscommon root | |
| 1249 | Real values in a quadratic relation | Medium | Hall & Knight | quadratic equationsdiscriminant+1 | |
| 1250 | Bounds for variables in a quadratic relation | Medium | Hall & Knight | quadratic equationsdiscriminant+1 | |
| 1254 | Radical exponent equation | Medium | Hall & Knight | fractional exponentssubstitution | |
| 1260 | Quintic Radical Powers | Medium | Hall & Knight | rational exponentsquadratic form | |
| 1267 | Product of binomials equation | Medium | Hall & Knight | polynomial equationsrearrangement of factors | |
| 1268 | Quartic equation by grouping factors | Medium | Hall & Knight | polynomial equationsrearrangement of factors | |
| 1269 | Solve Quartic Equation | Medium | Hall & Knight | quartic equationfactor grouping | |
| 1270 | Solve Polynomial Equation | Medium | Hall & Knight | polynomial equationgrouping factors | |
| 1271 | Radical Equation Substitution | Medium | Hall & Knight | radical equationsubstitution | |
| 1272 | Radical Equation with Quadratic Form | Medium | Hall & Knight | radical equationsubstitution | |
| 1273 | Radical Equation Reduction | Medium | Hall & Knight | radical equationsubstitution | |
| 1274 | Radical and Quadratic Equation | Medium | Hall & Knight | radical equationsubstitution | |
| 1275 | Rationalizing radical equation | Medium | Hall & Knight | radical equationsextraneous roots | |
| 1277 | Difference of radicals | Medium | Hall & Knight | radical equationsfactoring | |
| 1278 | Sum of three square roots | Medium | Hall & Knight | radical equations | |
| 1280 | Homogeneous radical equation with parameter | Medium | Hall & Knight | radical equationsparametric equations | |
| 1281 | Radical Equation Substitution | Medium | Hall & Knight | radicalssubstitution+1 | |
| 1282 | Radical Equation Sum | Medium | Hall & Knight | radicalssubstitution+1 | |
| 1283 | Radical Difference Equation | Medium | Hall & Knight | radicalsquadratic equations | |
| 1287 | Reciprocal quartic equation | Medium | Hall & Knight | quartic equationsubstitution+1 | |
| 1288 | Symmetric quartic equation | Medium | Hall & Knight | quartic equationsubstitution+1 | |
| 1289 | Radical equation with parameter | Medium | Hall & Knight | radical equationscomponendo and dividendo | |
| 1290 | Square root ratio equation | Medium | Hall & Knight | radical equationscomponendo and dividendo | |
| 1292 | Sum of radicals equation | Medium | Hall & Knight | radical equationssimplification | |
| 1517 | Real roots of quadratic equation 1 | Medium | Hall & Knight | discriminantquadratic equations+1 | |
| 1518 | Real roots of quadratic equation 2 | Medium | Hall & Knight | discriminantquadratic equations+1 | |
| 1519 | Rational roots of quadratic equation 1 | Medium | Hall & Knight | discriminantrational roots | |
| 1521 | Symmetric function of roots part 1 | Medium | Hall & Knight | roots of a quadraticVieta's formulas+1 | |
| 1522 | Symmetric function of roots part 2 | Medium | Hall & Knight | roots of a quadraticVieta's formulas+1 | |
| 1523 | Symmetric functions of roots (Part 1) | Medium | Hall & Knight | symmetric functions of rootsVieta's formulas | |
| 1524 | Symmetric functions of roots (Part 2) | Medium | Hall & Knight | symmetric functions of rootsVieta's formulas | |