Identify the coefficients: a = 2 , b = 3 , and c = − 10 .
Apply the quadratic formula: w = 2 a − b ± b 2 − 4 a c .
Substitute the values and simplify: w = 2 ( 2 ) − 3 ± 3 2 − 4 ( 2 ) ( − 10 ) = 4 − 3 ± 89 .
State the two exact solutions: w = 4 − 3 ± 89 .
Explanation
Understanding the Problem We are given the quadratic equation 2 w 2 + 3 w − 10 = 0 . Our goal is to find the exact solutions for w , without using decimals. We can use the quadratic formula to solve for w .
Applying the Quadratic Formula The quadratic formula is given by w = 2 a − b ± b 2 − 4 a c where a = 2 , b = 3 , and c = − 10 .
Substituting Values Substitute the values of a , b , and c into the quadratic formula: w = 2 ( 2 ) − 3 ± 3 2 − 4 ( 2 ) ( − 10 )
Simplifying the Discriminant Simplify the expression under the square root: 3 2 − 4 ( 2 ) ( − 10 ) = 9 + 80 = 89
Finding the Solutions Therefore, the solutions are: w = 4 − 3 ± 89
Exact Solutions The two solutions are: w = 4 − 3 + 89 and w = 4 − 3 − 89 These are the exact solutions for w .
Examples
Quadratic equations are incredibly useful in various real-world scenarios. For instance, imagine you're designing a rectangular garden and you know the total area and the relationship between the length and width. You can use a quadratic equation to determine the exact dimensions of the garden. Similarly, in physics, quadratic equations are used to model projectile motion, helping to calculate the trajectory of a ball thrown in the air or the path of a rocket. Understanding how to solve these equations allows you to make accurate predictions and informed decisions in these and many other practical situations.