SOLUTION: Hi there I need to calculate out how far and high a boy named Jose throws in a ball in a football match, Y stands for the height in meters and X for the diatance in meters from whe

Algebra.Com
Question 750622: Hi there I need to calculate out how far and high a boy named Jose throws in a ball in a football match, Y stands for the height in meters and X for the diatance in meters from where jose is standing.
How do I calculate Y=-0,04x^2+0,6x+2

Answer by nerdybill(7384)   (Show Source): You can put this solution on YOUR website!
Y=-0.04x^2+0.6x+2
.
Maximum is at vertex:
x-value of vertex is "axis of symmetry":
x = -b/(2a)
x = -0.6/(2*(-0.04))
x = -0.6/(-0.08)
x = 0.6/(0.08)
x = 7.5
Max height:
Y=-0.04(7.5)^2+0.6(7.5)+2
Y= 4.25 meters (max height)
.
Max distance, we set Y to zero and solve for x:
0=-0.04x^2+0.6x+2
0=0.04x^2-0.6x-2
0=0.02x^2-0.3x-1
applying the "quadratic formula" yields:
x = {17.81, -2.81}
throw out the negative solution (extraneous) leaving
x = 17.81 meters (max distance)
.
details of "quadratic formula":
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation (in our case ) has the following solutons:



For these solutions to exist, the discriminant should not be a negative number.

First, we need to compute the discriminant : .

Discriminant d=0.17 is greater than zero. That means that there are two solutions: .




Quadratic expression can be factored:

Again, the answer is: 17.8077640640442, -2.80776406404415. Here's your graph:

RELATED QUESTIONS

I am having trouble figuring out how to connect what I know about quadratic equations to... (answered by josgarithmetic)
A person standing close to the edge on the top of a 195-foot building throws a baseball... (answered by Alan3354)
a person throws a ball upward into the air with an initial velocity of 15.0 m/s. a)... (answered by mananth)
if a football match ball is kicked thrice by all 11 players in 1 hour then calculate % of (answered by rfer)
height y (in feet) of punted football is approximated by y = -16/2025 x^2 +9/5x + 5/2... (answered by Alan3354)
A student throws a ball vertically up with a speed of 33 m/s. a.) How high will the ball (answered by Alan3354)
Hi there I need help figuring out what's to do for the following question. The path... (answered by Alan3354)
A child throws a ball upward from the roof of a house. The tragctory is parabolic,... (answered by ankor@dixie-net.com)
At a football match, there are 29 800 people, correct to the nearest 100. (i) At the end... (answered by math_tutor2020,greenestamps)