f(x)=-2x^2-4x
Without using Calculus, we can find the x coordinate of the vertex by ... x = -b/2a......where, in this case, b= -4 and a = -2.....so we have
x = -b/2a = -(-4) / 2(-2) = 4 / -4 = -1
Now, to find the "y" coordinate of the vertex, just put -1 back into the function for each "x" and evalute the result......
So you will have.... -2(-1)^2 - 4(-1) = 'y"
Can you take it from here???
f(x)=-2x^2-4x
Without using Calculus, we can find the x coordinate of the vertex by ... x = -b/2a......where, in this case, b= -4 and a = -2.....so we have
x = -b/2a = -(-4) / 2(-2) = 4 / -4 = -1
Now, to find the "y" coordinate of the vertex, just put -1 back into the function for each "x" and evalute the result......
So you will have.... -2(-1)^2 - 4(-1) = 'y"
Can you take it from here???