Solve the Quadratic Equation: Finding X in 7x + 1 + (2x + 3)^2 = (4x + 2)^2

Question

Find X

7x+1+(2x+3)2=(4x+2)2 7x+1+(2x+3)^2=(4x+2)^2

Video Solution

Solution Steps

00:00 Find X
00:03 Open parentheses properly using shortened multiplication formulas
00:22 Calculate the squares and products
00:41 Arrange the equation so that the right side equals 0
00:50 Group terms
01:02 Simplify as much as possible
01:13 Identify the coefficients
01:22 Use the roots formula to find possible solutions
01:36 Substitute appropriate values and solve for solutions
01:41 Calculate the square and products
01:52 And this is the solution to the question

Step-by-Step Solution

To solve the equation 7x+1+(2x+3)2=(4x+2)2 7x + 1 + (2x + 3)^2 = (4x + 2)^2 , we follow these steps:

  • Step 1: Expand both sides using the square of a binomial formula.
  • Step 2: Simplify the equation to form a standard quadratic equation.
  • Step 3: Use the quadratic formula to find the roots of the equation.

Step 1: Expand the squares.

The left side: (2x+3)2=4x2+12x+9 (2x + 3)^2 = 4x^2 + 12x + 9 .

The right side: (4x+2)2=16x2+16x+4 (4x + 2)^2 = 16x^2 + 16x + 4 .

Step 2: Substitute back into the original equation and simplify:

7x+1+4x2+12x+9=16x2+16x+4 7x + 1 + 4x^2 + 12x + 9 = 16x^2 + 16x + 4 .

Combine like terms:

4x2+19x+10=16x2+16x+4 4x^2 + 19x + 10 = 16x^2 + 16x + 4 .

Step 3: Move all terms to one side:

4x2+19x+1016x216x4=0 4x^2 + 19x + 10 - 16x^2 - 16x - 4 = 0 .

Which simplifies to:

12x2+3x+6=0-12x^2 + 3x + 6 = 0 .

Step 4: Divide by -3 to simplify:

4x2x2=0 4x^2 - x - 2 = 0 .

Step 5: Use the quadratic formula:

x=b±b24ac2a x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} , where a=4 a = 4 , b=1 b = -1 , c=2 c = -2 .

Calculate the discriminant:

b24ac=(1)244(2)=1+32=33 b^2 - 4ac = (-1)^2 - 4 \cdot 4 \cdot (-2) = 1 + 32 = 33 .

Calculate the roots:

x=1±338 x = \frac{1 \pm \sqrt{33}}{8} .

Therefore, the solution to the problem is x=1±338 x = \frac{1 \pm \sqrt{33}}{8} .

Answer

1±338 \frac{1\pm\sqrt{33}}{8}