All categories

2 years ago

Evaluate 3xy²-y³ for x=-1 and y=2.help.

Mathematics

2 answers:

yanalaym [24]2 years ago

7 0

The answer to this problem is -20

Annette [7]2 years ago

7 0

Step-by-step explanation:

=3xy²-y³

=3(-1)(2)²-(2)³

=3(-1)(4)-(8)

= -12-8

= -20

hope it helps.

You might be interested in

Como se saca la raíz cuadrada?

Maslowich

Answer:

La raíz cuadrada de cualquier número se puede expresar usando la fórmula: √y = y½.

8 0

3 years ago

A circle has a diameter with endpoints at (6, 5) and (8, 5). Write the equation for the circle.

mario62 [17]

Answer:

$(x-7)^2+(y-5)^2=1$

Step-by-step explanation:

The two things that are required to formulate the equation of the circle is the center coordinate and the radius of the circle!

Center of the circle:

The center of the circle always lies at the midpoint of the endpoints of its diameter: Let's call the endpoints A(6,5) and B(8,5).

Using the midpoint formula we'll get:

$(x_m, y_m) = \left(\dfrac{x_1+x_2}{2},\dfrac{y_1+y_2}{2}\right)$

$(x_m, y_m) = \left(\dfrac{6+8}{2},\dfrac{5+5}{2}\right)$

$(x_m, y_m) = (7,5)$

This is the center coordinate of our circle.

Radius:

The radius of the circle is the distance from the center of the circle to any of the endpoints of the diameter (A or B)

We can use the distance formula:

$r = \sqrt{(x_1-x_2)^2+(y_1-y_2)^2}$

$r = \sqrt{(x_1-x_m)^2+(y_1-y_m)^2}$

$r = \sqrt{(6-7)^2+(5-5)^2}$

$r = \sqrt{1^2}$

$r = 1$

Equation of the circle:

The equation is written as:

$(x-a)^2+(y-b)^2=r^2$

here, (a,b) are the center points of the circle

in our case this is $(a,b)=(x_m,y_m)=(7,5)$

and r = 1

$(x-7)^2+(y-5)^2=1^2$

$(x-7)^2+(y-5)^2=1$

This is the equation of the circle!

3 0

3 years ago

If a sample of pure sodium has a mass of 8.2 grams and sodium has an average atomic mass of 22.99 g/mol, how many sodium atoms a

Nonamiya [84]

8.2 grams = 1 mol
Na ________
22.99 grams

First multiply the value of 8.2 to 1. Then divide by the value of 22.99 to determine the number of moles of sodium present in the 8.2 gram sample.

Then use the following equation to solve for sodium atoms.

Number of moles of Na • Avogadro Number = Number of sodium atoms.

0.3566782 • (6.02 X 10^23). = 2.1472 X 10 ^ 23. Or 2.15 X 10 ^ 23.

The answer is the second option - 2.15 X 10 ^ 23.

7 0

3 years ago

(FASTEST AND BEST ANSWER GETS BRAINLIEST)1

Semmy [17]

Answer:

Step-by-step explanation:

6 0

2 years ago

lisa has played in 6 soccer matches. Her brother josh has played in 18 soccer matches. lisa saay josh has played in 12 times as

Basile [38]

Answer:

Josh has played 12 matches more, not 12 times as many as her.

Step-by-step explanation:

Lisa said times, making the statement incorrect.

5 0

3 years ago

Evaluate 3xy²-y³ for x=-1 and y=2.help.​

Evaluate 3xy²-y³ for x=-1 and y=2.help.