Recall the equation for projectiles is y = –16x2 + vx + s, where y is the object’s current height (in feet) at any time after it is projected, x is the time (in seconds) the object has been in the air, v is the object’s starting upward velocity, and s is the object’s starting height.

Question

blurbendy · Answer

what is the question

anonymous · Answer

use graphing technology to complete this activity since many of the solutions will most likely involve irrational numbers. @blurbendy

blurbendy · Answer

Okay, is there a question where we can use the formula y = -16x^2 + vx + s, or are we just supposed to graph the formula on its own?

anonymous · Answer

were just supposed to graph it on our own

blurbendy · Answer

Okay, do you have a basic graph Cartesian graph drawn in front of you (a graph with an x-axis and a y-axis)?

anonymous · Answer

yes

blurbendy · Answer

Okay, we need starting values for x, v, and s.  Let's start with x = 1, v = 2, and s = 3.

What does the equation become when you substitute these values into those variables?

anonymous · Answer

y=-16x^2+2(1)+3

blurbendy · Answer

close

y = -16(1)^2 = -16
So,

y = -16+2 +5
y = -9

blurbendy · Answer

So, on your graph, you can put a point at (1, -9)

blurbendy · Answer

Don't worry about s or v since they are constants

blurbendy · Answer

Keep putting in values for x and see what you get for y (you should see a pattern)

anonymous · Answer

i think i understand now, omg thank you so much!!

blurbendy · Answer

Any time!