Answer:
(-2 , 5)
(-1 , 0)
(1 , -4)
(3 , 0)
(4 , -5)
Step-by-step explanation:
First solve the equation:
x² - 2x - 3
Find two numbers with have a sum of -2 and a product of -3.
-3 and 1
(x - 3)(x + 1)
Solve for x:
x - 3 = 0
x = 3
x + 1 = 0
x = -1
You know that the graph will cross the x-axis at -1 and 3.
(-1 , 0)
(3 , 0)
You know that the graph is positive.
Complete the square to find the vertex
x² - 2x - 3
(x - 1)² = x² - 2 + 1
x² - 2x - 3 = x² - 2 + 1 - 2 = (x - 1)² - 2
1 = 0
x = 1
Substitute into the original equation:
x² - 2x - 3 =
1² - (2 * 1) - 3 =
1 - 2 - 3 =
-4
(1 , -4)
You can input any two numbers within -10 and 10. Such as -2 and 4.
x² - 2x - 3 =
-2² - (2 * -2) - 3 =
4- -4- 3 =
5
(-2 , 5)
x² - 2x - 3 =
4² - (2 * 4) - 3 =
16 - 8 - 3 =
-5
(4 , -5)
