Answer:
(- 1, - 4 ) and x = - 1
Step-by-step explanation:
given a parabola in standard form
y = ax² + bx + c ( ax≠ 0 )
then the x- coordinate of the vertex is
x = - [tex]\frac{b}{2a}[/tex]
y = x² + 2x - 3 ← is in standard form
with a = 1, b = 2 , then
x = - [tex]\frac{2}{2}[/tex] = - 1
substitute x = - 1 into the equation for corresponding y- coordinate
y = (- 1)² + 2(- 1) - 3 = 1 - 2 - 3 = - 4
vertex = (- 1, - 4 )
this is an upward opening parabola ( a > 0 )
the axis of symmetry is a vertical line passing through the vertex with equation
x = c ( c is the value of the x- coordinate of the vertex ), then equation is
x = - 1
