The line of symmetry for the quadratic equation y = ax^2 + 8x - 3 is x = 4. what is the value of "a"?

a = - 1

Step-by-step explanation:

given a quadratic in standard form : y = ax² + bx + c : a ≠ 0

Then the x-coordinate of the vertex is

• = -

The line of symmetry passes through the parabola, hence x-coordinate is 4

y = ax² + 8x - 3 is in standard form

with a = a, b = 8 and c = - 3, hence

- = 4 ( multiply both sides by 2a

- 8 = 8a ( divide both sides by 8 )

a = - 1

answer: i'm not going to give you the answer, but some hints to work it out.

step-by-step explanation: so, if there is a straight line that means that the line angle is 180°. so we subtract the 2 angle measures provided, (15 and 38) from 180. so the answer is 180 - (38 + 15). (you have to solve the equation)