What two numbers multiply to negative 64 and add up to 16

What two numbers multiply to negative 64 and add up to 16

The Correct Answer and Explanation is:

To solve for two numbers that multiply to -64 and add up to 16, let’s denote these numbers as xxx and yyy. According to the problem:x×y=−64x \times y = -64x×y=−64x+y=16x + y = 16x+y=16

To solve this system, we can use substitution or trial and error. However, let’s first approach this by setting up a quadratic equation.

If we consider the two numbers as the roots of a quadratic equation, then the sum and product of the roots can be used to form the quadratic equation. The general form of a quadratic equation is:t2−(x+y)t+x×y=0t^2 – (x + y)t + x \times y = 0t2−(x+y)t+x×y=0

Substituting the values for the sum and product from the problem:t2−16t−64=0t^2 – 16t – 64 = 0t2−16t−64=0

Now we need to solve this quadratic equation. To do this, we use the quadratic formula:t=−b±b2−4ac2at = \frac{-b \pm \sqrt{b^2 – 4ac}}{2a}t=2a−b±b2−4ac​​

For the equation t2−16t−64=0t^2 – 16t – 64 = 0t2−16t−64=0, the coefficients are:

  • a=1a = 1a=1
  • b=−16b = -16b=−16
  • c=−64c = -64c=−64

Substitute these values into the quadratic formula:t=−(−16)±(−16)2−4(1)(−64)2(1)t = \frac{-(-16) \pm \sqrt{(-16)^2 – 4(1)(-64)}}{2(1)}t=2(1)−(−16)±(−16)2−4(1)(−64)​​t=16±256+2562t = \frac{16 \pm \sqrt{256 + 256}}{2}t=216±256+256​​t=16±5122t = \frac{16 \pm \sqrt{512}}{2}t=216±512​​t=16±22.6272t = \frac{16 \pm 22.627}{2}t=216±22.627​

Now, solve for the two possible values of ttt:t1=16+22.6272=38.6272≈19.31t_1 = \frac{16 + 22.627}{2} = \frac{38.627}{2} \approx 19.31t1​=216+22.627​=238.627​≈19.31t2=16−22.6272=−6.6272≈−3.31t_2 = \frac{16 – 22.627}{2} = \frac{-6.627}{2} \approx -3.31t2​=216−22.627​=2−6.627​≈−3.31

Thus, the two numbers are approximately 19.31 and -3.31. When multiplied, they give approximately -64, and when added together, they give approximately 16.

However, exact integer values would require adjusting the approach slightly. Would you like help with that?

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