The generic equation of a parabola is:
f (x) = ax ^ 2 + bx + c
To verify the equation of the parabola you need three points:
f (x) = ax ^ 2 + bx + c
We choose the points:
(x, y) = (- 1,7)
7 = a (-1) ^ 2 + b (-1) + c
7 = a - b + c
(x, y) = (0,5)
5 = a (0) ^ 2 + b (0) + c
5 = c
(x, y) = (- 2,5)
5 = a (-2) ^ 2 + b (-2) + c
5 = 4a - 2b + c
We solve:
c = 5
5 = 4a - 2b + 5
7 = a - b + 5
Rewriting
b = 2a
a-b = 2
Substituting:
a-2a = 2
a = -2
b = -4
The equation of the parabola is:
f (x) = - 2x ^ 2 -4x + 5
Answer:
A I think
Step-by-step explanation:
Answer:
C
Step-by-step explanation:
So we have:
To simplify, we can use the quotient rule of exponents, which says that if we have:
Then this equals:
So, our equation will be:
Subtract the exponents. Turn 1/5 into 2/10 by multiplying both layers be 2. Thus:
Subtract in the exponent:
So, our answer is C :)
Answer: (A) y=-2x
Step-by-step explanation:
Lets plug in the point (2,-4) for each equation.
-4=-2(2) this is correct
-4=2*2
-4=4 This cannot be true
-4=-2+3 =-4=1 This is false
Lastly, -4=2-4 this is false because -4 can't equal to -2.
So, A is the answer
Answer: B : 12+3=15
Step-by-step explanation:
A sum is the answer of an addition problem
