An algebraic expression is a phrase in mathematics that consists of numbers such as 1,2,3 and the like, variables which are represented with letters and operations like addition, multiplication, subtraction and division. It is usually used to represent a certain situation which would relate the variables involved. To write the algebraic expression for the problem statement above, we do as follows:

Let x = number of consoles to be bought
y = number of games to be bought
z = number of controllers to bebought
C = total cost of all

The total cost would be equal to the sum of the price multiplied by the number of consoles, games and controllers bought. We write the algebraic expression as follows,

C = 299x + 59.99y + 29.99z

4 0

3 years ago

the initial vertical velocity of a rocket shot straight up is 42 meters per second. How long does it take for the rocket to retu

Snowcat [4.5K]

It takes 4.3 seconds for the rocket to return to earth.

The equation is:
$0=-9.8t^2+v_0t+h_0$
where -9.8m/sec² is the acceleration due to gravity, v₀ is the initial velocity, and h₀ is the initial height. We will go from the assumption that the rocket is launched from the ground, so h₀=0, and we are told that the initial velocity, v₀, is 42. This gives us:

$0=-9.8t^2+42t$

We will use the quadratic formula to solve this. The quadratic formula is:
$x=\frac{-b\pm \sqrt{b^2-4ac}}{2a}$

Plugging in our information we have:
$t=\frac{-42\pm \sqrt{42^2-4(-9.8)(0)}}{2(-9.8)}
\\
\\=\frac{-42\pm \sqrt{1764-0}}{-19.6}
\\
\\=\frac{-42\pm \sqrt{1764}}{-19.6}
\\
\\=\frac{-42\pm 42}{-19.6}=\frac{-42-42}{-19.6} \text{ or } \frac{-42+42}{-19.6}
\\
\\=\frac{-84}{-19.6}\text{ or }\frac{0}{-19.6}
\\
\\=4.3\text{ or }0$

x=0 is when the rocket is launched; x=4.3 is when the rocket lands.

8 0

3 years ago

V = (pi r^2 h/3)...solve for h

guapka [62]

Answer:

h = (3×V)/ (pi×r²)

Step-by-step explanation:

$v = \frac{\pi {r}^{2} h}{3}$