Answer:
b = y-intercept; The equation is y = mx + b. The x and y variables remain as letters, but m and b are replaced by numbers (ex: y = 2x + 4, slope = 2 and y-intercept = 4). The following video will show a few examples of understanding how to use the slope and intercept from an equation.
Vertex (4, -13) y = x^2 - 8x + 3 x-coordinate of vertex: x = -b/(2a) = 8/2 = 4 y-coordinate of vertex: y(4) = 16 - 32 + 3 = -13 Vertex (4, -13) To find y-intercepts, make x = 0 --> y = 3 To find x-intercepts, solve the quadratic equation y = 0 Use the improved quadratic formula D = d^2 = b^2 - 4ac = 64 - 12 = 52 --> d = +- 2sqrt13 There are 2 x-intercepts (2 real roots): x = -b/(2a) +- d/(2a) = 8/2 +- (2sqrt13)/2 = 4 +- sqrt13 graph{x^2 - 8x + 3 [-40, 40, -20, 20]}
Step-by-step explanation:
