Solve Complex Equation: (x+8)(8-x) + 4(x-3)(x+3) + 5(6-x²) = 0

Question

Solve the following equation:

(x+8)(8x)+4(x3)(x+3)+5(6x2)=0 (x+8)(8-x)+4(x-3)(x+3)+5(6-x^2)=0

Video Solution

Solution Steps

00:00 Solve
00:03 Use the commutative law
00:26 Use the shortened multiplication formulas
00:56 Calculate 8 squared
01:00 Expand the parentheses
01:30 Calculate the multiplications
01:36 Collect like terms
01:57 Isolate X
02:05 Break down 29 into square root of 29 squared
02:11 Again use the shortened multiplication formulas
02:20 Find the two possible solutions
02:39 And this is the solution to the question

Step-by-Step Solution

To solve the equation (x+8)(8x)+4(x3)(x+3)+5(6x2)=0 (x+8)(8-x)+4(x-3)(x+3)+5(6-x^2)=0 , we will follow these steps:

  • Step 1: Expand and simplify each factor using important algebraic formulas.
  • Step 2: Combine all terms to form a quadratic equation.
  • Step 3: Solve the quadratic equation using the quadratic formula.

Let's work through each step:

Step 1: Expand each part of the equation:

  • The first term (x+8)(8x) (x+8)(8-x) is a difference of squares, which simplifies to:
    (x+8)(8x)=(82x2)=64x2 (x+8)(8-x) = (8^2 - x^2) = 64 - x^2 .
  • The second term 4(x3)(x+3) 4(x-3)(x+3) is another difference of squares:
    4[(x29)]=4x236 4[(x^2 - 9)] = 4x^2 - 36 .
  • The third term 5(6x2) 5(6-x^2) simplifies to:
    305x2 30 - 5x^2 .

Step 2: Combine the results to form a quadratic equation:

Combine terms in the equation:

64x2+4x236+305x2=0 64 - x^2 + 4x^2 - 36 + 30 - 5x^2 = 0

Simplify further:

(4x2x25x2)+(6436+30)=0 (4x^2 - x^2 - 5x^2) + (64 - 36 + 30) = 0

2x2+58=0 -2x^2 + 58 = 0

Rearrange to standard quadratic form:

2x2=58 2x^2 = 58

Step 3: Solve using the quadratic formula:

The equation simplifies to x2=29 x^2 = 29 .

Taking the square root of both sides gives the solutions:

x=±29 x = \pm \sqrt{29} .

Thus, the solution to the equation is ±29 \pm \sqrt{29} .

Answer

±29 ±\sqrt{29}