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Write the function 3x2 -12x + 61 in
vertex form.

User Teratorn
by
4.6k points

1 Answer

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Answer:

y=3(x-2)²+49

Explanation:

vertex-form is given as y=a(x-h)²+k, where (h,k) is the coordinate of the vertex

we are given the function in standard form, which is:

y=ax²+bx+c

our function is:

3x²-12x+61

the value of a is given as the value of the coefficient in front of the squared term (in this case, it's 3)

here's the function so far in vertex form:

y=3(x-h)²-k

now, we need to find the vertex

to find h, we can use the formula (-b/2a)

the value of b is given as the value of the coefficient in front of the linear term (in this case, it's -12)

and we know from above that a=3

substitute what we know into the formula:

h=-b/2a

h=12/2(3)

h=12/6

h=2

so h is 2

*Please note that when we substitute it into the function, it's -2

so here is our function so far:

y=3(x-2)²-k

now to find k, which is given in the formula c-(b²/4a)

we know from above that a=3, b=-12

c is the value of the constant (term without a variable). In this case, it's 61

once again, substitute what we know into the equation:

k=61-((-12)²/4(3))

k=61-(144/12)

k=61-12

k=49

therefore the function will be:

y=3(x-2)²+49

Hope this helps!

User Yinqiu
by
5.4k points