Question

Find the equation of a quadratic function in general form whose graph has points: (-2, 3) (0, 3) and (-4,-5).

Answer 1

Answer:

-x²-2x+3

Step-by-step explanation:

The first thing I noticed is that the first and second point has the same y intercept despite being only 2 x coordiantes away. This must mean that the vertex's x coordiante is probably (-1,4)

Because the vertex is probably (-1,4) the graph must also be concave down because the point (-4,-5) is below it

writing this in vertex form we get

-a(x+1)²+4

Where a is some constant

solve for a by plugging in (0,3)

3= -a(0+1)²+4

3= -a+4

-1= -a

a=1

therefore the equation looks like

-(x+1)²+4

expanding this so that it's in stantard form...

-(x²+x+x+1)+4

-x²-2x+3

which is the final answer