The standard deviatiion is the square root of the variance.
Answer:
a=2(s-5)
a(your age): 20
Step-by-step explanation:
a stands for your age
s stands for sister
a=2(s-5)
1-substitute 15 for s a=2(15-5)
2- a=2(10)
the 15-5 stands for sisters age minus five which gives you brothers age, 10. You multiply it by two because your brother is half your age.
3-a=20
check your work:
because your brother is 10 and you are 20, he is half your age (10/20 can be simplified to 1/2)
Hope this helped, if you have any other questions please lmk!
Answer:
Width of T.V. is 21.94 inches Height is 39 inches and area is 855.66 square inch.
Step-by-step explanation:
When we buy an electronic item like T.V or Blue Ray aspect ratio is the term which is used by the salesmen or technicians. Aspect ratio is actually the ratio of length and breadth of the screen of a device or ration of width and height.
In this question aspect ratio of television is given as 16:9
This can be written as
or 
Screen of the T.V. is 65 inch which is the diagonal length of the screen.
We know from pythagoras theorem in a right angle triangle




Now height of the T.V.will be

now area of the T.V.=W×H=39×21.94=855.66 square inch