Solve the Quadratic Equation: 81x² - 216 + 144 = 0

Question

Solve the following equation:

81x2216+144=0 81x^2-216+144=0

Video Solution

Solution Steps

00:00 Find X
00:03 Pay attention to the coefficients
00:10 Use the roots formula
00:15 Substitute appropriate values according to the given data and solve for X
00:49 Calculate the products and the square
01:21 And this is the solution to the question

Step-by-Step Solution

To solve the quadratic equation 81x2216x+144=0 81x^2 - 216x + 144 = 0 , we begin by identifying the coefficients: a=81 a = 81 , b=216 b = -216 , and c=144 c = 144 .

Next, we use the quadratic formula:

x=b±b24ac2a x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}

Substitute the values of a a , b b , and c c into the formula:

b24ac=(216)2481144 b^2 - 4ac = (-216)^2 - 4 \cdot 81 \cdot 144

=4665646656=0 = 46656 - 46656 = 0

The discriminant is zero, indicating there is exactly one real solution. Substitute back into the quadratic formula:

x=(216)±0281 x = \frac{-(-216) \pm \sqrt{0}}{2 \cdot 81}

x=216±0162 x = \frac{216 \pm 0}{162}

x=216162 x = \frac{216}{162}

Simplify the fraction:

x=216÷54162÷54=43 x = \frac{216 \div 54}{162 \div 54} = \frac{4}{3}

Therefore, the solution to the equation is x=43 x = \frac{4}{3} .

By comparing with the given choices, choice 1: x=43 x = \frac{4}{3} is correct.

Answer

x=43 x=\frac{4}{3}