Answer:
y = - 8x² + 6
Step-by-step explanation:
The equation of a parabola in vertex form is
y = a(x - h)² + k
where (h, k) are the coordinates of the vertex and a is a multiplier
Here (h, k) = (0, 6), thus
y = a(x - 0)² + 6, that is
y = ax² + 6
To find a substitute (- 1, - 2) into the equation
- 2 = a(- 1)² + 6, that is
- 2 = a + 6 ( subtract 6 from both sides )
- 8 = a
y = - 8x² + 6
slope intercept form
y=mx+b
where m is the slope and b is the y intercept
if we change from point slope form
y-y1 = m(x-x1)
we distribute
y-y1 = mx -x*x1
then add y1 to each side
y = mx -x*x1+y1
remember x and y are variables and should stay in the equation
m,x1,y1 are numbers from the problem
you may have to calculate the slope (m) from the formula
m = (y2-y1)/(x2-x1) from two points on the line
1. Given (12+3)x, we can sum the numbers in the parenthesis to get 15x
2. Given 12x+3x, we can factor x to get (12+3)x and get the same as 1.
3. Given (12+3x)x, we have to distribute the x and we have 
4. This expression is already simplified.
