Question

For the equation y<or equal to -x^2+3x+10 I got the vertex (3/2, 67/4). Is this right?

Answer 1

-(x^2 - 3/2) + 10
-(x^2 - 3/2 + 9/4) + 10 + 9/4
-(x - 3/2)^2 + 49/4

Looks like (3/2,49/4) to me

Answer 2

the x is correct, but

y = -(3/2)^2 + 3(3/2) + 10
= -9/4 + 9/2 + 10
= 49/4

remember in -x^2, you have to square, then multiply by -1, so the result is negative

you are confusing -x^2 with (-x)^2

Answer 3

wow - sorry about my typos. Only the 3rd line of my post is correct.
-(x^2 - 3x + (3/2)^2) is better