We have two congruent trapezoids.
The formula of an area of a trapezoid:

We have:

Substitute:

Answer:

Answer: 2x and y= 4+
Step-by-step explanation:
x = 2 times 2 and so on....
y = 4 plus 4 plus 4 etc....
Answer:
7/165
Step-by-step explanation:
We take number after the decimal point 042
then we subtract the non repeating.In this case is 0 so we not subtract anything
This will be the numerator 42
For each repeating decimal we write a 9 (in this case 2 nines)
For each non repeating decimal we write a zero
Denominator is 990
42/990 = 7/165
7:165 = 0.0424242
I think this is what you do. Hope it helps!
1.326 grams of NH3 are required to produce 4.65 g of HF.
Step-by-step explanation:
Balanced chemical reaction is written first to know the number of moles taking part in original reaction.
NH3 +3 F2 ⇒3 HF + NF3
Given:
mass of HF = 4.65
First the number of moles of HF in 4.65 grams is calculated by using the formula:
number of moles (n) = 
atomic mass of HF = 20 grams/mole
putting the values in the above equation number of moles can be found.
n = 
= 0.235 moles of HF are given.
From the equation it can be said that:
1 mole of NH3 reacts to form 3 moles of HF
so, x moles of NH3 would react to form 0.235 moles of HF
= 
3x = 0.235
x = 
x = 0.078 moles of NH3 is required.
The moles are converted to mass by applying the formula:
mass = atomic mass X number of moles (atomic mass of NH3 = 17 grams/mole)
putting the values in the formula
mass = 17 X 0.078
mass = 1.326 grams
Answer:
236 cm²
Step-by-step explanation:
Height of an equilateral triangle (h) = √3 /2 (l)
l = side of the equilateral triangle.
h = √3 /2 (15)
In an equilateral triangle the orthocenter, centroid, circumcenter and incenter are in the same spot
The center of the circle is the centroid and height match with the median. The radius of the circumcircle is equal to two thirds the height.
Formula for the Radius of the circumcircle = 2/3 h
= 2/3 x √3 /2 (15)
= 5 √3 cm (=radius)
Area of the circle = πr^
= 3.14 x( 5 √3 ) ^
=3.14 x(25*3)
=3.14 x 75
=235.5
=236 cm²