Solve the Polynomial Equation: 3x³ - 10x² + 7x = 0 for X

Question

3x310x2+7x=0 3x^3-10x^2+7x=0

Video Solution

Solution Steps

00:07 Let's find the value of X.
00:11 First, break down X cubed into factors of X squared and X.
00:16 Now, break down X squared into X and X.
00:22 Next, identify the common factor.
00:29 Take the common factor out of the parentheses.
00:40 Determine what makes each factor zero.
00:43 Great! That's one solution.
00:47 Now, let's find what makes the entire expression in parentheses zero.
00:55 Break down 10 into 3 and 7.
01:01 Remove common factors outside the parentheses.
01:07 Identify the common factor again.
01:15 Find what makes each factor zero in the product.
01:19 Excellent! This is the second solution.
01:22 Let's isolate X for the final solution.
01:31 And there you have it, the solution to our question!

Step-by-Step Solution

To solve the problem 3x310x2+7x=0 3x^3 - 10x^2 + 7x = 0 , follow these steps:

  • Step 1: Factor out the greatest common factor (GCF). The common factor in all terms is x x . Factoring out x x gives:

x(3x210x+7)=0 x(3x^2 - 10x + 7) = 0

  • Step 2: Apply the Zero Product Property. Set each factor equal to zero:

x=0 x = 0 or 3x210x+7=0 3x^2 - 10x + 7 = 0

  • Step 3: Solve the quadratic equation 3x210x+7=0 3x^2 - 10x + 7 = 0 using the quadratic formula:

The quadratic formula is x=b±b24ac2a x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} . Here, a=3 a = 3 , b=10 b = -10 , c=7 c = 7 .

Calculate the discriminant:

b24ac=(10)24(3)(7)=10084=16 b^2 - 4ac = (-10)^2 - 4(3)(7) = 100 - 84 = 16

Since the discriminant is a perfect square, this quadratic has rational roots. Using the quadratic formula gives:

x=(10)±166=10±46 x = \frac{-(-10) \pm \sqrt{16}}{6} = \frac{10 \pm 4}{6}

Thus, the solutions are:

x=10+46=146=73 x = \frac{10 + 4}{6} = \frac{14}{6} = \frac{7}{3}

x=1046=66=1 x = \frac{10 - 4}{6} = \frac{6}{6} = 1

  • Step 4: Combine all solutions. The solutions to the original equation are:

x=0 x = 0 , x=1 x = 1 , and x=73 x = \frac{7}{3} .

Therefore, the solution to the problem is x=0,1,73 x = 0, 1, \frac{7}{3} .

Answer

x=0,1,73 x=0,1,\frac{7}{3}