144t-16t^2= 16t(9-t)
after 3 seconds (just substitute t=3):
16(3)(9-3)=
16(3)(6)=
16*18=
288
maximum height: find the average of the roots:
the roots of 16t(9-t) are t=0 or t=9
since it's a parabola, the maximum is at t=4.5, at 324 ft
if its height is 224 feet, the equation is 224=144t-16t^2
16t^2-144t+224=0
divide by 16: t^2-9t+14=0
this can be factored as (t-2)(t-7)=0
the roots are t=2 and t=7, so the ball has been in the air for either 2 seconds or 7 seconds
the roots to 144t-16t^2 are 0 and 9, so the ball will hit the ground 9 seconds after being thrown
Answer:
Step-by-step explanation:
um
Only 1 whole acre and it you want to be technical you can plant 1.3 acres. Just divide
Answer:
The Discriminant is 25
Step-by-step explanation:
For this case, the discriminant will be given by
b ^ 2 - 4 * a * c
Where
b = 7
a = 3
c = 2
substituting
b ^ 2 - 4 * a * c = (7) ^ 2 - 4 * (3) * (2) = 25
Therefore the value of the discriminant is 25.
How many x-intercepts does this function have?
It has two intercepts with the x axis and can be found by equaling the function to zero. That is to say,
3x2 + 7x + 2 = 0
The results will be the interceptions with x.
What are the number of zeros for this function?
The number of zeros for this function is
two real number solutions
Because it is a quadratic function.
Answer:
Kevin needs 96 points on his last test to raise his mean test score to 90 points.
Step-by-step explanation:
we know that
The mean score is the total of all scores divided by the total number of tests.
Let
x_1 ----> the score in the first math test
x_2 ----> the score in the second math test
x_3 ----> the score in the third math test
x_4 ----> the score in the fourth math test
we have
After taking the first 3 tests, his mean test score is 88 points
so

----> equation A
How many points does he need on his last test to raise his mean test score to 90 points?
so

----> equation B
substitute equation A in equation B

solve for x_4


Therefore
Kevin needs 96 points on his last test to raise his mean test score to 90 points.