1.
the x value of the vertex in form
ax^2+bx+c=y
is
-b/2a
so
-2x^2+8x-18
x value of vertex is
-8/(2*-2)=-8/-4=2
plug it in to get y value
-2(2)^2+8(2)-18
-2(4)+16-18
-8-2
-10
vertex is at (2,-10)
or you could complete the square to get into y=a(x-h)^2+k, where the vertex is (h,k)
so as follows
y=(-2x^2+8x)-18
y=-2(x^2-4x)-18
y=-2(x^2-4x+4-4)-18
y=-2((x-2)^2-4)-18
y=-2(x-2)^2+8-18
y=-2(x-2)^2-10
vertex is (2,-10)
5.
vertex is the time where the speed is the highest
at about t=10, the speed is at its max
Answer:
use demos
Step-by-step explanation:
2. The absolute value of -8 is 8. True
3. An isosceles triangle has three congruent sides.
Nope. It has two
4. The cosine is the ratio between the length of the opposite leg to the length of the hypotenuse.
I have no idea.
5. The boiling point of water is 212°C.
true
6.
The expression 28xyz has 4 terms.
true
7.
Shapes that have the same size and shape are said to be similar.
false
8.
The points where the sides of a polygon meet are called the vertexes.
true
9. A heptagon is a seven-sided polygon.
true (hexagon)
10.
An acute angle has more than 90° but less than 180°.
true
Y=-2x+4 and y=-2x-5 (mark brainliest plss)
I think it's 182 I'm not completely sure though
