The line of symmetry for the quadratic equation y = ax2 - 2x - 3 is x = 1. What is the value of "a"?

Y = a (x - h) ² + k • (h, k) is the vertex • x = h is line of symmetry so y = ax² - 2x - 3 y/a = x² - 2/ax - 3/a y/a + 3/a = x² - 2/ax y/a + 4/a = x² - 2/ax + (-1/a) ² ← completing the square y/a + 4/a = (x - 1/a) ² y/a = (x - 1/a) ² - 4/a y = a (x - 1/a) ² - 4 so since you've been given h = 1 then 1/a = 1 and so a = 1