Question

Write an inequality then solve. Use x as a variable.

Four times the sum of a number and 15 is at least 120.
A) 4(x + 15) ≥ 120, x ≥ 21
B) 4(x + 15) ≤ 120, x ≤ 21
C) 4(x + 15) ≥ 120, x ≤ 21
D) 4(x + 15) ≤ 120, x ≥ 21

Answer 1

To write the inequality, we need to translate the statement into mathematical language. Four times the sum of a number and 15 is at least 120 can be written as: 4(x + 15) ≥ 120. To solve the inequality, we can divide both sides by 4 to isolate the x: x + 15 ≥ x ≥ 15. Therefore, the correct answer is A) 4(x + 15) ≥ 120, x ≥ 21.

Step-by-step explanation:

To write the inequality, we need to translate the statement into mathematical language. Four times the sum of a number and 15 is at least 120 can be written as: 4(x + 15) ≥ 120. To solve the inequality, we can divide both sides by 4 to isolate the x: x + 15 ≥ 30. Then, we subtract 15 from both sides to get the final solution: x ≥ 15. Therefore, the correct answer is A) 4(x + 15) ≥ 120, x ≥ 21.