Answer:

Step-by-step explanation:

Answer:
Step-by-step explanation:
-5x+31+3x=3
move everthing to one side
-5+31+3x-3=0
add and subtract common terms
-2x+28=0
divide across by common denominator
-x+14=0
Solve for x
x=14
In this sum we will calculate using the simple interest.
Simple interest is calculated from the formula :
I = PRT
where I is the interest, P is the principal, R is interest rate per year and t is time in years.
I = 2000 × 3 % x 2
We have to turn 3% to its decimal fraction which is 0.03, so:
I = 2000 × 0.03 × 2
I = 60 × 2
I = 120
Therefore the interest earned in two years will amount to 120 $
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