Question

Which value of x makes the inequality 2(8 – x) < 4 true? A. x = –16 B. x = –9 C. x = 4 D. x = 10

Answer 1

Answer:

10

Step-by-step explanation:

If we plug in any negative number as x, the result will always be greater than 4, which rules out answers A and B

lets try plugging in 4 as x to test answer C:

2(8-4)

2(4)= 8

8 is greater than 4, therefore C is wrong.

Lets try 10 as X (answer D):

2(8-10)

2(-2)

-4

We know that -4 is less than 4, therefore it makes the inequality true! :)

Answer 2

2(8 - x) < 4

Instead of testing each individual value of the inequality, let's solve it to determine which value makes it true.

Let's start by dividing both sides by 2.

2(8 - x)/2 < 4/2

8 - x < 2

Subtract both sides by 8

8 - x - 8 < 2 - 8

-x < -6

Multiply/Divide both sides by -1 (either one works)

[NOTE: Remember to reverse the inequality sign when dividing/multiplying by a negative number!]

x > 6

Thus, any x value that's greater than 6 will make the inequality true. That would be answer choice D. Happy studying~