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2 years ago

An atom of a certain element has 21 protons, 21

1 answer:

3 0

45-21=24 neutrons :)

As the generally accepted mass of an electron is 0. So, to find the mass of neutrons, minus the protons from the total mass.

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Two of the vertices of a rectangle are (1, −6) and (−8, −6). If the rectangle has a perimeter of 26 units, what are the coordina

pantera1 [17]

Answer: $(x_1,y_1)=(1,-2)$

$(x_2,y_2)=(-8,-2)$

Step-by-step explanation:

Given

Co ordinates of vertices(1,-6) and (-8,-6)

When two points is given then Length of two points is given by

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

$L=\sqrt{\left ( 1-\left ( -8\right )\right )^2+\left ( -6+6\right )^2}$

$L=\sqrt{9^2}=9 units$

Perimeter of rectangle is =26 units

Let the other side be x

thus

$2\left ( x+9\right )=26$

x+9=13

x=4 units

therefore to get the other two co ordinates

such that the length of that side is 4 units is

$(x_1,y_1)=(1,-2)$

$(x_2,y_2)=(-8,-2)$

Horizontal distance will remain same only vertical distance will change in given co ordinates to obtain the remaining two co ordinates

To verify the above two distance between two points must be 13 units

6 0

3 years ago

Answer ASPA! PLEASE

qwelly [4]

Answer:

Step-by-step explanation:

The correct answer is C. not skewed

They are equal on both sides.

7 0

3 years ago

Explain why the exponents cannot be added in the product 12^3 and 11^3

GrogVix [38]

Because bases are different.

a^n · a^m = a^(n+m)

4 0

3 years ago

The trapezoid in the figure has equal nonparallel sides. The upper base is 6, the lower base is 16, and the diagonal is 12. What

____ [38]

To find this I would use the pythagorean theorem which is:

a^2 + b^2 = c^2

Since we already know c = hypotenuse, and a side of the shorter sides we can plug them it like this:

11^2 + b^2 = 12^2

121 + b^2 = 144

b^2 = 23

√23 = 4.79

Round:

B. 4.8 would be your answer!

5 0

3 years ago

721 + 19 = 886 + 33 - 447 22= 915 + 36 = ??

timama [110]

Answer:

Step-by-step explanation:

5 0

2 years ago

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