Answer:
For t=3 sec the velocity change from positive to negative
Step-by-step explanation:
we have
This is the equation of a vertical parabola open downward (the leading coefficient is negative)
where
s(t) is the distance in feet
t is the time in seconds
We know that
To find out when the velocity change from positive to negative, we need to determine the turning point of the quadratic equation
The turning point of the quadratic equation is the vertex
so
Convert the quadratic equation into vertex form
Factor -16
Complete the square
Rewrite as perfect squares
The vertex is the point (3,244)
therefore
For t=3 sec the velocity change from positive to negative
you add them together to get 8/8 and that simplifies to 1
Let t be the number of tolls they crossed.
Amount they spent at each toll = $1.75.
Amount they spent at gas station = $28.
Let C be the total amount they spent on gas and tolls.
If they crossed 1 toll, then
C = 28 + 1.75(1).
If they crossed 3 tolls, then,
C = 28 + 1.75(3)
If they crossed t tolls, then,
C = 28 + 1.75t
Here, the terms are 28 and 1.75t and the factors are 1.75 and t.
Answer:36 postcards
Step-by-step explanation:
jenny bought 12 post cards
joe bought half of the postcards jenny bought = 12/2 = 6
ruth bought 3 times the postcards joe bought = 3 x 6 = 18
total postcards bought by all = 12 + 6 + 18 = 36 postcards
There are different ways to solve a quadratic equation, the main ones that i'm thinking about right now are:
1) factor the equation as a product:
ex: x^2+ 4x + 3 =0
(x+3) (x+1) = 0
x=-3 and x=-1 are the solutions.
To find (x+p) and (x+q) you have to think that (p+q )have to be equal to the number that is multiplied by x, in my example it was 4 (3+1=4), (p times q) have to be equal to the last number of the quadratic equation, the one that is not multiplied by any x, that in my example is 3 (3 x 1= 3)
2) The other way to solve a quadratic function is by using a formula:
given: ax^2 +bx +c=0
x= (-b +/- <span>√(b^2 -</span> 4ac)) / 2a
ex: 3x^2 + 4x -2=0
x= (-4 +/- √16-4(3)(-2)) / 6= (-4 +/- √16+24)/6= (-4 +/- <span>√40) / 6
now there are 2 possibilities: x= (-4+</span><span>√40) /6
and
x= (-4 - </span><span>√40) / 6
I hope the examples were clear enough also if i did't get very nice numbers. Look closely to the sings + and -, they are very important</span>
