It would be this. -2x and 2x cancel out, leaving you with fx=-1
12h-9h=3h move everything else to other side
3h=20-40+6
3h=-14
divide by 3
h=-14/3
Answer:
The pebble will hit the ground 8.29 second after it is thrown.
Step-by-step explanation:
Given that,
The height of the pebble after t seconds is given by the equation
h= -16t²+24 t+900.
When the pebble hit the ground, the height of the pebble will be zero.
So putting h=0 in the given equation.
0 = -16t²+24 t+900
⇒-4(4t²-6t-225)=0
⇒4t²-6t-225=0
Applying quadratic formula
, here a=4, b= -6 and c= -225.

⇒ t = 8.29, -6.79
Since time can not negative.
∴t=8.29 seconds.
The pebble will hit the ground 8.29 second after it is thrown.
Answer:
16 and -4
Step-by-step explanation:
Let the 2 numbers be x and y with x > y
x+y=12
x-y=20
Adding the 2 equations, term by term on both sides, will eliminate y leaving an equation in x that we can solve
(x+x)+(-y+y)=(12+20)
2x=32
x=16
16+y=12
y=-4
16+-4=12
12=12
16--4=20
20=20
Answer:
$2662.5 is the answer in my opinion