which of the following equations represents a parabola that opens up and has a vertex with a positive x-value?
a. y=-x^2+8x-15
b. y=2x^2-16x+38
c. y=2x^2+16x+24
d. y=-4x^2-14x-12

Opens up means in y=ax^2+bx+c form, a is positive
not A or D
vertex witha positive x value

for y=ax^2+bx+c
the x value of the vertex is -b/2a

test b and c
B. 2x^2-16x+38
-b/2a=-(-16)/2=16/2=8, that is positive

C. 2x^2+16x+24
-b/2a=-16/2=-8, negative

B is the answer

To solve which ordered pair lie on the graph of the given function f(x) = 128(0.5^2)

You mus substitute each ordered pair then check if it satisfy the given function

(0,1)

1 = 128(0.5^0)

1 = 128 so wrong

(1, 64)

64 = 128(0.5^1)

64 = 64 correct

(3, 16)

16 = 128(0.5^3)

16 = 16 correct

0.5 = 128(0.5^8)

0.5 = 0.5 correct