If y = 2x² − 2x + 4, what is y when x = 5?

Substitute the value carefully, squaring only what's squared, then evaluate term by term. The correct answer is 44. Traps to avoid: 14 comes from the "squared as doubled" error; 36 comes from the "sign error constant" error; 94 comes from the "squared the coefficient" error; 64 comes from the "sign error middle term" error.