Math  /  Algebra

QuestionWhich of the following equations hav exactly one solution?
Choose all answers that apply: A 2x31=2x312 x-31=2 x-31 B 2x31=2x312 x-31=-2 x-31 (c) 2x+31=2x312 x+31=2 x-31 (D) 2x2=2x312 x-2=2 x-31

Studdy Solution

STEP 1

What is this asking? Which of these equations have only *one* solution for xx? Watch out! Some equations can have *no* solutions or *infinitely many* solutions!
Don't fall for that trap!

STEP 2

1. Analyze Equation A
2. Analyze Equation B
3. Analyze Equation C
4. Analyze Equation D

STEP 3

Alright, let's **start** with equation A: 2x31=2x312x - 31 = 2x - 31.
This looks interesting!

STEP 4

Notice that both sides of the equation are *exactly* the same.
This means no matter what value we plug in for xx, the equation will *always* be true!

STEP 5

For example, if x=0x = 0, we get 31=31-31 = -31.
If x=1x = 1, we get 29=29-29 = -29.
See? Always true!
So, equation A has **infinitely many** solutions, not just one.

STEP 6

Now, let's **move on** to equation B: 2x31=2x312x - 31 = -2x - 31.

STEP 7

Let's **add** 2x2x to both sides to **group** the xx terms: 2x31+2x=2x31+2x2x - 31 + 2x = -2x - 31 + 2x, which simplifies to 4x31=314x - 31 = -31.

STEP 8

Next, let's **add** 31 to both sides to **isolate** the xx term: 4x31+31=31+314x - 31 + 31 = -31 + 31, which simplifies to 4x=04x = 0.

STEP 9

Finally, let's **divide** both sides by 4 to **solve** for xx: 4x14=0144x \cdot \frac{1}{4} = 0 \cdot \frac{1}{4}, which gives us x=0x = 0.
One solution!
Awesome!

STEP 10

Time for equation C: 2x+31=2x312x + 31 = 2x - 31.

STEP 11

Let's **subtract** 2x2x from both sides: 2x+312x=2x312x2x + 31 - 2x = 2x - 31 - 2x, which simplifies to 31=3131 = -31.
Uh oh!
That's not right!

STEP 12

Since 31 is *never* equal to -31, this equation has **no** solutions.
Tricky!

STEP 13

Last but not least, equation D: 2x2=2x312x - 2 = 2x - 31.

STEP 14

Let's **subtract** 2x2x from both sides: 2x22x=2x312x2x - 2 - 2x = 2x - 31 - 2x, which simplifies to 2=31-2 = -31.
Nope, that's not true either!

STEP 15

So, equation D also has **no** solutions.

STEP 16

Only equation B, 2x31=2x312x - 31 = -2x - 31, has exactly **one** solution, which is x=0x = 0.

Was this helpful?

Studdy solves anything!

banner

Start learning now

Download Studdy AI Tutor now. Learn with ease and get all help you need to be successful at school.

ParentsInfluencer programContactPolicyTerms
TwitterInstagramFacebookTikTokDiscord