The axis of symmetry is also defined by the following equation:
x = -b/2a
Remember, a quadratic function has the following form:
y = ax2 + bx + c
Follow 4 steps to use an equation to calculate the line of symmetry for y = x2 + 2xIdentify a and b for y = 1x2 + 2x. a = 1; b = 2Plug into the equation x = -b/2a. x = -2/(2*1)
Simplify. x = -2/2The line of symmetry is x = -1.