Question

Which of the following sets shows all the numbers from the set {1, 2.5, 3, 4.5, 5} that make the inequality 3a + 4 ≥ 13 true?

{2.5, 3, 4.5}
{1, 2.5}
{3, 4.5, 5}
{4.5, 5}

Answer 1

c. {3, 4.5, 5}

3(3) + 4 ≥ 13
9 + 4 ≥ 13
13 ≥ 13
true

3(4.5) + 4 ≥ 13
13.5 + 4 ≥ 13
17.5 ≥ 13
true
3(5) + 4 ≥ 13
19 ≥ 13
true