Answer:
Error is in step 2
Step-by-step explanation:
Harry is trying to solve the equation y = 2x^2 − x − 6 using the quadratic formula. He has made an error in one of the steps below.
Step 1: [tex]x= \frac{-(-1)+-\sqrt{(-1)^2-4(2)(-6)} }{2(2)}[/tex]
Step 2: [tex]x= \frac{-(-1)+-\sqrt{-1+48}}{2(2)}[/tex]
Step 3: [tex]x= \frac{-(-1)+-\sqrt{47}}{2(2)}[/tex]
Step 4: [tex]x= \frac{1+-\sqrt{47}}{4}[/tex]
Quadratic formula is
[tex]x= \frac{-(b)+-\sqrt{(b)^2-4(a)(c)} }{2(a)}[/tex]
From the given equation a= 2, b= -1 and c= -6
plug in all the values in the formula
Step 1: [tex]x= \frac{-(-1)+-\sqrt{(-1)^2-4(2)(-6)} }{2(2)}[/tex]
Step 1 is correct
(-1)^2 = -1 times -1 = +1 (negative times negative is positive)
Instead of +1 , Harry used -1 inside the square root
So the error is in step 2
Step 2: [tex]x= \frac{-(-1)+-\sqrt{1+48}}{2(2)}[/tex]
