Solve the Quadratic Equations: x² + 9 = 0 and 2x² + 8 = 0 Compared

Question

Solve each equation separately and find which x is the largest.

  1. x2+9=0 x^2+9=0

  2. 2x2+8=0 2x^2+8=0

Video Solution

Solution Steps

00:10 Let's find the largest value of X.
00:13 First, we're going to work on section one. Let's solve for X here.
00:18 Our goal is to isolate X, step by step.
00:22 Remember, any number squared is always zero or more.
00:26 But, negative nine is less than zero. So, no solution for section one.
00:34 Now, let's move on to section two to find X.
00:38 Again, we'll isolate X to see what we can find.
00:46 Just like before, any number squared is zero or more.
00:52 Minus four is less than zero, so there's also no solution here.
00:58 And that's how we figure out this problem!

Step-by-Step Solution

To solve this problem, we'll follow these steps:

  • Step 1: Solve the equation x2+9=0 x^2 + 9 = 0
  • Step 2: Solve the equation 2x2+8=0 2x^2 + 8 = 0
  • Step 3: Compare the solutions (if any) to identify the largest x x

Step 1: Solving x2+9=0 x^2 + 9 = 0 :
First, isolate x2 x^2 by subtracting 9 9 from both sides:
x2=9 x^2 = -9 .
Since x2=9 x^2 = -9 , trying to find the square root leads to x=±9 x = \pm \sqrt{-9} ,
which involves the imaginary unit i i , hence no real solution exists.

Step 2: Solving 2x2+8=0 2x^2 + 8 = 0 :
First, isolate 2x2 2x^2 by subtracting 8 8 from both sides:
2x2=8 2x^2 = -8 .
Divide each side by 2 2 :
x2=4 x^2 = -4 .
Attempting to take the square root results in x=±4 x = \pm \sqrt{-4} ,
which similarly involves the imaginary unit i i , so no real solution exists.

Step 3: Compare the solutions:
Since both equations yield no real solutions, there is no value of x x to compare.

Therefore, there is no solution to the two equations.

Answer

There is no solution to the two equations