Answer:
s = height above ground
s = 60 + 20 t - 4.9 t^2 (standard physics equation on earth)
at t = 0
s = 60 (clearly :)
now when does it hit the bleak earth?
That is when s = 0
4.9 t^2 - 20 t -60 = 0
solve quadratic and use the positive t (the negative t was back before you threw it if you had thrown it from the ground)
t = 6.09 or - 2.01
use t = 6.09
now to do the last part there are two obvious ways to get t at the peak
1. look for vertex of parabola
2. look for halfway between t = -2.01 and t = 6.09
I will do it the hard (11) waay by completing the square
4.9 t^2 - 20 t = -(s-60)
t^2 - 4.08 t = -.204 s + 12.2
t^2 - 4.08 t +2.04^2 = -.204 s +12.2 + 4.16
(t-2.04)^2 = -.204(s-80.2)
so
top at 80.2 meters at t = 2.04 s
===============
quick check on time
should be average of 6.09 and -2.01
=4.08 /2 = 2.04 check
Answer:
15x + 20y
Step-by-step explanation:
First, we need to combine like terms,
10x + 20y + 5x
15x + 20y
Since x and y are different variables, we cannot combine them, meaning that the answer is,
15x + 20y
Answer:
bet but need barinlyist
Step-by-step explanation:
Answer:
Step-by-step explanation:
3y+5y=8y
8y=7(divide 8 in both sides to get y)
y=7/8
x+2y=3...but we already know the value of y, so substitute 7/8 to y
x+2(7/8)=3
x+14/8=3
x=3-14/8
=1.25
Answer:
x = 15
Step-by-step explanation:
3x− 12 = 2x+ 3
3x-2x-12 = 3
x = 3+12
x=15
hope this helps! :)
