The first one is (-2,1)
The other one is 36
Answer:
It takes 2.8 seconds for the ball to fall 215 ft.
Step-by-step explanation:
We are given a position function s(t) where s stands for the number of feet the ball has fallen, so we have to replace s with the given value of 215 ft and solve for the time t.
Setting up the equation.
The motion equation is given by

We can replace there s = 215 ft to get

Solving for the time t.
From the previous equation we can move all terms in one side to get

At this point we can solve for t using quadratic formula.

where a, b and c are the coefficients of the quadratic equation

So we get

Replacing on the quadratic formula we get

Using a calculator we get

Physically speaking the only result that makes sense is to move forward in time that give us t = 2.8 seconds.
We can conclude that it takes 2.8 seconds for the ball to fall 215 ft.
Answer:
The correct option is D.
Step-by-step explanation:
The given equation is

According to the addition property of equality
and
are equivalent equations.
Use addition property of equality, add 3x on both the sides.


Therefore Sam's work is incorrect because he make calculation mistake.
According to the subtraction property of equality
and
are equivalent equations.
Use subtraction property of equality, subtract 5x from both the sides.


Therefore Roy's work is correct because he used subtraction property.
Option D is correct.
Answer:11
Step-by-step explanation