Introduction to Inequalities with Two Variables

Which of the following is a linear inequality in two variables?

• 4a -4 < 5a

• 7a -4 > 5

• 3jk² - 4 > 9

• 5 + 4b < 5c

Which of the following ordered pairs is not the solution for the inequality 3x - 2y ≥ 15 ?

• (7, 3)

• (6, 1)

• (5, 0)

• (4, 5)

Diagram 2 shows two straight lines on a Cartesian plane. Which of the following regions define linear inequalities

y ≤ x + 5 and y ≥ 2 − x?

• I

• II

• III

• IV

Which of the following sets of linear inequalities defines the shaded region in Diagram 3?

• y ≥ 4 − x, y + 2x ≤ 8 and y < 4

• y ≥ 4 − x, y + 2x ≥ 8 and y < 4

• y ≤ 4 − x, y + 2x ≥ 8 and y > 4

• y ≤ 4 − x, y + 2x ≤ 8 and y > 4

The diagram shows a shaded region that satisfies three inequalities. State an inequality other than x < 4 and y ≥ −x.

• x ≤ o

• x ≥ 0

• y ≤ 0

• y ≥ 0

Kim is using two mobile networks. Network one charges RM0.30 for every minute of call and network two charges RM0.38 for every minute of call. Kim spends at least RM68 monthly for calls. Which of the following inequalities is best to represent Kim's situation?

• 0.30x + 0.38y < 68

• 0.30x + 0.38y > 68

• 0.30x + 0.38y ≤ 68

• 0.30x + 0.38y ≥ 68

Diagram 4 shows the shaded region R on a Cartesian plane. Which of the following linear inequalities does not define the shaded region R?

• x + y ≥ 4

• x − y ≥ −2

• y < 3

• x < 3

Which of the following graphs shows the correct shaded region for 5x + 3y ≥ 5, y ≥ x and y ≤ 3?

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x male students and y female students are participating a motivation camp. Which of the following linear inequalities is correct?

• At least 50 students are participating the camp, x + y > 50

• The number of female students exceeding the number of male students is not more than 5, y − x ≤ 5

• At most 30 female students are participating the camp, y ≥ 30

• The number of female students that are participating the camp is more than the number of male students, x ≥ y

Which of the following graphs represent the inequality

x + y ≤ 5 ?

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