Question

Using the properties of inequalities, write down the inequality that you will get if you: add the number –5; 2.7; 7; to both sides of the inequality 18>−7. subtract the number 2; 12; −5; from both sides of the inequality 5>−3. multiply both sides of the inequality −9 −6 by the number 3; −3; −1.

Answer 1

Using the properties of inequalities

if you add −5, to both sides of the inequality 18>−7.

the inequality is 13 > -12

Do that with all of them

if you add 2.7, to both sides of the inequality 18>−7. the inequality is 20.7 > -4.3

if you add 7, to both sides of the inequality 18>−7. the inequality is 25 > 0

Hope this helps! Sorry thats not all of them. -Viki

Answer 2

See below

Explanation:

1..........................

• 18 >−7

Add –5; 2.7; 7 to both sides

• 18 -5 > -7 - 5 ⇒ 13 > -12
• 18 + 2.7 > - 7 + 2.7 ⇒ 20.7 > - 43
• 18 + 7 > -7 + 7 ⇒ 25 > 0

2..........................

• 5 > -3

Subtract 2; 12; -5 from both sides

• 5 - 2 > -3 -2 ⇒ 3 > - 5
• 5 - 12 > -3 - 12 ⇒ -7 > -15
• 5 -(-5) > -3 - (-5) ⇒ 10 > 2

3..........................

• - 9 < -6

Multiply both sides by 3; −3; −1

When multiplying both sides of inequality by positive number the sign stays as is, when multiplying both sides of inequality by negative number the sign reverses

• -9 *3 < -6*3 ⇒ -27 < - 18
• -9*(-3) > -6*(-3) ⇒ 27 > 18
• -9*(-1) > -6*(-1) ⇒ 9 > 6