Register
Given that 4x^2-32x-20+k is a perfect square find k​
72.8k views
4 votes
Given that 4x^2-32x-20+k is a perfect square find k​

User Zholen
by
4.5k points

1 Answer

5 votes

Answer:

  • k = 20

Explanation:

Perfect square identity:

  • (a + b)² = a² + 2ab + b²

Completing the square:

  • 4x² - 32x - 20 + k =
  • (2x)² - 2*2x*8 + 8² - 20 + k =
  • (2x - 8)² - (20 - k)

In order the given to be a perfect square, we need:

  • 20 - k = 0
  • k = 20

User Kiet Tran
by
4.6k points
Ask a Question
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

4.9m questions

6.4m answers

Other Questions

Pizza planet is running a special 3 pizzas for 16.50. What is the unit rate for one pizza
If the 9-inch wheel of cheese costs $18.60, what is the cost per square inch? If the cost is less than a dollar, put a zero to the left of the decimal point?
I need to simplify this expression.
Which property is shown in the problem below? -8(x-3y-9) = -8x+24y+72 A the associative property B the commutative property C the distributive property D the division property ASAP
What is the domain and range?
Link Copied!