Question

pakai cara ya kakk, poinnya banjirr​

Answer 1

f(x) = ax^2 + bx + c.

A(1,-9)

-9 = a(1)^2 + b(1) + c

-9 = a + b + c

B(2,-8)

-8 = a(2)^2 + b(2) + c

-8 = 4a + 2b + c

C(3,-5)

-5 = a(3)^2 + b(3) + c

-5 = 9a + 3b + c.

-9 = a + b + c

-9 - a - b = c

4a + 2b + c = -8

4a + 2b - 9 - a - b = -8

3a + b = --8 + 9

3a + b = 1

9a + 3b + c = -5

9a + 3b - 9 - a - b = -5

8a + 2b = -5 + 9

8a + 2b = 4

3a + b = 1

6a + 2b = 2

8a + 2b = 4

6a + 2b = 2

----------------- -

2a = 2

a = 2/2

a = 1.

3a + b = 1

3 + b = 1

b = 1 - 3

b = -2.

c = -9 - a - b

c = -9 - 1 - (-2)

c = -9 - 1 + 2

c = -10 + 2

c = -8

f(x) = ax^2 + bx + c

f(x) = 1x^2 + (-2)x + (-8)

f(x) = x^2 - 2x - 8.

a. y = x^2 - 2x - 8.