中等MATH-INEQ-011
Solve 5 − 2x < 1.
A. x < 2
B. x < −2
C. x > −2
D. x > 2✓ 答案
解說
Subtract 5 to get −2x < −4. Divide by −2 and reverse the sign: x > 2. Test x = 3: 5 − 6 = −1 < 1, which holds. Test x = 1: 5 − 2 = 3, which is not less than 1.
Subtract 5 to get −2x < −4. Divide by −2 and reverse the sign: x > 2. Test x = 3: 5 − 6 = −1 < 1, which holds. Test x = 1: 5 − 2 = 3, which is not less than 1.