Vertex form => y = a(x-h)^2 + k, where (h,k) is center of vertex.
You have,
y = -3x^2 + 6x - 1
#Factor -3
y = -3(x^2 - 2x + 1/3)
#Pull out the -3 * 1/3, and add the 1 to make a perfect square trio-nominal, however you cannot randomly add -3 * 1, so you must also add 3 * 1, so in a sense you're adding 0.
y = -3(x^2 - 2x + 1) + (-3 * 1/3) + (3 * 1)
#Simply and factor the perfect square trio-nomial
y = -3(x - 1)^2 + (-1 + 3)
y = -3(x-1)^2 + 2
Alternative way:
You know y = ax^2 + bx^2 + c, so you know a = -3
To find the center the x coordinate is given by x = -b / (2a) = -6 / (-3 * 2) = 1
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Verified answer
Vertex form => y = a(x-h)^2 + k, where (h,k) is center of vertex.
You have,
y = -3x^2 + 6x - 1
#Factor -3
y = -3(x^2 - 2x + 1/3)
#Pull out the -3 * 1/3, and add the 1 to make a perfect square trio-nominal, however you cannot randomly add -3 * 1, so you must also add 3 * 1, so in a sense you're adding 0.
y = -3(x^2 - 2x + 1) + (-3 * 1/3) + (3 * 1)
#Simply and factor the perfect square trio-nomial
y = -3(x - 1)^2 + (-1 + 3)
y = -3(x-1)^2 + 2
Alternative way:
You know y = ax^2 + bx^2 + c, so you know a = -3
To find the center the x coordinate is given by x = -b / (2a) = -6 / (-3 * 2) = 1
Then find the y by plugging that value of x:
y(1) = -1 + 6(1) + -3(1)^2 = -1 + 6 - 3 = 2
y = a(x-h)^2 + k
a = -3
h = 1
k = 2
Gives you the same answer.