Quick and explain. i'm offering 20pts (more than it's worth) and brainliest answser

Step-by-step explanation:

(a) when there is a negative in front of the leading coefficient  (- x^2), that is a reflection over the x axis.  a regular parabola opens up.  In this case, the negative in front of the first term makes it open downward.  

-f(x) is a reflection    so -2x^2 would open downward.

(b) the vertex of the parabola is -b/2a

in this problem a x^2 + bx + c = y

                         -2x^2 + 4x + 3 = y

a = -2, b = 4, c = 3

formula for vertex -b/2a  = -4/2(-2)    = -4/-4  = 1    This is the x-value of the vertex.  Plug back into original equation to find the y value.

(1, ?)    -2(1)^2 + 4(1) + 3 = 5

vertex is (1,5) and is above the x axis

pls ask

3x + 4y -25 =0 represents the amount of change sianna should recieve