The parabola y=ax^2+bx+c is graphed below. Find a+b+C. (The grid lines are one unit apart.)
The vertex is (2,1)
And we have the form
y = a(x - h)^2 + k where ( h, k) is the vertex
And the point (0, 5) is on the graph....so...
5 = a ( 0 - 2)^2 + 1
5 - 1 = 4a
4 = 4a
a = 1
So we have
y= 1( x - 2)^2 + 1
y = x^2 - 4x + 4 + 1
y = x^2 - 4x + 5
a = 1 b = -4 c = 5
a + b + c = 1 - 4 + 5 = 2