Find The Number To Add To $x^2 - 12x$ To Make It A Perfect Square Trinomial. Write That Trinomial As The Square Of A Binomial.A. Add 12; $(x - 6)^2$ B. Add 144; \$(x - 12)^2$[/tex\] C. Add $36$; $(x

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What is a Perfect Square Trinomial?

A perfect square trinomial is a quadratic expression that can be factored as the square of a binomial. It has the form (x+a)2(x + a)^2 or (x−a)2(x - a)^2, where aa is a constant. Perfect square trinomials are important in algebra because they can be used to solve quadratic equations and to simplify expressions.

The Formula for a Perfect Square Trinomial

The formula for a perfect square trinomial is (x+a)2=x2+2ax+a2(x + a)^2 = x^2 + 2ax + a^2 or (x−a)2=x2−2ax+a2(x - a)^2 = x^2 - 2ax + a^2. To find the missing number to make a trinomial a perfect square, we need to identify the value of aa.

Finding the Missing Number

Let's consider the trinomial x2−12xx^2 - 12x. We want to find the number to add to make it a perfect square trinomial. To do this, we need to identify the value of aa in the formula (x−a)2=x2−2ax+a2(x - a)^2 = x^2 - 2ax + a^2.

Option A: Add 12

If we add 12 to the trinomial x2−12xx^2 - 12x, we get x2−12x+12x^2 - 12x + 12. This can be factored as (x−6)2(x - 6)^2. However, this is not the correct answer because the original trinomial is x2−12xx^2 - 12x, not x2−12x+12x^2 - 12x + 12.

Option B: Add 144

If we add 144 to the trinomial x2−12xx^2 - 12x, we get x2−12x+144x^2 - 12x + 144. This can be factored as (x−12)2(x - 12)^2. However, this is not the correct answer because the original trinomial is x2−12xx^2 - 12x, not x2−12x+144x^2 - 12x + 144.

Option C: Add 36

If we add 36 to the trinomial x2−12xx^2 - 12x, we get x2−12x+36x^2 - 12x + 36. This can be factored as (x−6)2(x - 6)^2. However, this is not the correct answer because the original trinomial is x2−12xx^2 - 12x, not x2−12x+36x^2 - 12x + 36.

The Correct Answer

To find the correct answer, we need to use the formula (x−a)2=x2−2ax+a2(x - a)^2 = x^2 - 2ax + a^2. We know that the trinomial is x2−12xx^2 - 12x, so we can set up the equation x2−12x=x2−2ax+a2x^2 - 12x = x^2 - 2ax + a^2. Solving for aa, we get a=6a = 6. Therefore, the correct answer is to add 36 to the trinomial x2−12xx^2 - 12x to make it a perfect square trinomial.

Conclusion

In conclusion, a perfect square trinomial is a quadratic expression that can be factored as the square of a binomial. To find the missing number to make a trinomial a perfect square, we need to identify the value of aa in the formula (x−a)2=x2−2ax+a2(x - a)^2 = x^2 - 2ax + a^2. In this case, the correct answer is to add 36 to the trinomial x2−12xx^2 - 12x to make it a perfect square trinomial.

Example Problems

  1. Find the missing number to make the trinomial x2+14xx^2 + 14x a perfect square trinomial.
  2. Find the missing number to make the trinomial x2−20xx^2 - 20x a perfect square trinomial.
  3. Find the missing number to make the trinomial x2+18xx^2 + 18x a perfect square trinomial.

Solutions

  1. To find the missing number, we need to use the formula (x+a)2=x2+2ax+a2(x + a)^2 = x^2 + 2ax + a^2. We know that the trinomial is x2+14xx^2 + 14x, so we can set up the equation x2+14x=x2+2ax+a2x^2 + 14x = x^2 + 2ax + a^2. Solving for aa, we get a=7a = 7. Therefore, the missing number is 49.
  2. To find the missing number, we need to use the formula (x−a)2=x2−2ax+a2(x - a)^2 = x^2 - 2ax + a^2. We know that the trinomial is x2−20xx^2 - 20x, so we can set up the equation x2−20x=x2−2ax+a2x^2 - 20x = x^2 - 2ax + a^2. Solving for aa, we get a=10a = 10. Therefore, the missing number is 100.
  3. To find the missing number, we need to use the formula (x+a)2=x2+2ax+a2(x + a)^2 = x^2 + 2ax + a^2. We know that the trinomial is x2+18xx^2 + 18x, so we can set up the equation x2+18x=x2+2ax+a2x^2 + 18x = x^2 + 2ax + a^2. Solving for aa, we get a=9a = 9. Therefore, the missing number is 81.

Tips and Tricks

  1. To find the missing number, use the formula (x−a)2=x2−2ax+a2(x - a)^2 = x^2 - 2ax + a^2 or (x+a)2=x2+2ax+a2(x + a)^2 = x^2 + 2ax + a^2.
  2. Identify the value of aa in the formula.
  3. Solve for aa using the given trinomial.
  4. The missing number is the value of a2a^2.

Conclusion

Q: What is a perfect square trinomial?

A: A perfect square trinomial is a quadratic expression that can be factored as the square of a binomial. It has the form (x+a)2(x + a)^2 or (x−a)2(x - a)^2, where aa is a constant.

Q: How do I find the missing number to make a trinomial a perfect square?

A: To find the missing number, use the formula (x−a)2=x2−2ax+a2(x - a)^2 = x^2 - 2ax + a^2 or (x+a)2=x2+2ax+a2(x + a)^2 = x^2 + 2ax + a^2. Identify the value of aa in the formula and solve for aa using the given trinomial.

Q: What is the formula for a perfect square trinomial?

A: The formula for a perfect square trinomial is (x+a)2=x2+2ax+a2(x + a)^2 = x^2 + 2ax + a^2 or (x−a)2=x2−2ax+a2(x - a)^2 = x^2 - 2ax + a^2.

Q: How do I identify the value of aa in the formula?

A: To identify the value of aa, look at the given trinomial and compare it to the formula. The value of aa is the number that is being multiplied by xx in the trinomial.

Q: What is the missing number in the trinomial x2−12xx^2 - 12x?

A: To find the missing number, use the formula (x−a)2=x2−2ax+a2(x - a)^2 = x^2 - 2ax + a^2. We know that the trinomial is x2−12xx^2 - 12x, so we can set up the equation x2−12x=x2−2ax+a2x^2 - 12x = x^2 - 2ax + a^2. Solving for aa, we get a=6a = 6. Therefore, the missing number is 36.

Q: What is the missing number in the trinomial x2+14xx^2 + 14x?

A: To find the missing number, use the formula (x+a)2=x2+2ax+a2(x + a)^2 = x^2 + 2ax + a^2. We know that the trinomial is x2+14xx^2 + 14x, so we can set up the equation x2+14x=x2+2ax+a2x^2 + 14x = x^2 + 2ax + a^2. Solving for aa, we get a=7a = 7. Therefore, the missing number is 49.

Q: What is the missing number in the trinomial x2−20xx^2 - 20x?

A: To find the missing number, use the formula (x−a)2=x2−2ax+a2(x - a)^2 = x^2 - 2ax + a^2. We know that the trinomial is x2−20xx^2 - 20x, so we can set up the equation x2−20x=x2−2ax+a2x^2 - 20x = x^2 - 2ax + a^2. Solving for aa, we get a=10a = 10. Therefore, the missing number is 100.

Q: What is the missing number in the trinomial x2+18xx^2 + 18x?

A: To find the missing number, use the formula (x+a)2=x2+2ax+a2(x + a)^2 = x^2 + 2ax + a^2. We know that the trinomial is x2+18xx^2 + 18x, so we can set up the equation x2+18x=x2+2ax+a2x^2 + 18x = x^2 + 2ax + a^2. Solving for aa, we get a=9a = 9. Therefore, the missing number is 81.

Q: How do I know if a trinomial is a perfect square?

A: To determine if a trinomial is a perfect square, look at the formula (x+a)2=x2+2ax+a2(x + a)^2 = x^2 + 2ax + a^2 or (x−a)2=x2−2ax+a2(x - a)^2 = x^2 - 2ax + a^2. If the trinomial matches one of these formulas, then it is a perfect square.

Q: What are some common mistakes to avoid when finding the missing number?

A: Some common mistakes to avoid when finding the missing number include:

  • Not using the correct formula
  • Not identifying the value of aa correctly
  • Not solving for aa correctly
  • Not checking if the trinomial is a perfect square

Q: How do I practice finding the missing number?

A: To practice finding the missing number, try the following:

  • Use online resources or worksheets to practice finding the missing number
  • Work with a partner or tutor to practice finding the missing number
  • Use real-world examples to practice finding the missing number
  • Take practice quizzes or tests to assess your understanding of finding the missing number

Conclusion

In conclusion, finding the missing number to make a trinomial a perfect square trinomial requires the use of the formula (x−a)2=x2−2ax+a2(x - a)^2 = x^2 - 2ax + a^2 or (x+a)2=x2+2ax+a2(x + a)^2 = x^2 + 2ax + a^2. By identifying the value of aa and solving for aa, we can find the missing number. Remember to practice finding the missing number to become proficient in this skill.