Points a and b lie on a circle centered at point o. if oa=5 and lenth of ab/circumference=1/4 what is the area of sector aob? use the value pi =3.14

Since arc AB is 1/4 of the circumference, the central angle AOB will be 1/4 of a circle, so π/2 in radians. The area of a sector is given by

... A = (1/2)r²·θ

where θ is the central angle in radians and r is the radus.

The area is ...

... A = (1/2)·5²·π/2 = 25π/4

... A ≈ 19.625

The area of the sector is about 19.63 square units.

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explanation

the graph has a slope of 1/3 because each time you move up 1, you go to the right 3. so, slope = rise/run = 1/3. we can cross choice a off the list since we want a slope of 3, rather than 1/3.

the first table shown has a slope of -3. this is because the rise is -6 and the run is 2, so slope = rise/run = -6/2 = -3. note how x increases by 2 each time (run) and y drops by 6 each time (rise). choice b can be eliminated.

the second table has a slope of 3. each time x goes up by 1, the y values increase by 3. slope = rise/run = 3/1 = 3. alternatively you can use the slope formula to prove that the slope is 3 here. use any two rows of values to generate the two points. choice c is one of the answers

the third table also has a slope of 3. let's use the slope formula to prove as such. i'm going to use the first two rows of the table. so i'll use the two points (2,1) and (5,10)

m = slope

m = (y2-y1)/(x2-x1)

m = (10-1)/(5-2)

m = 9/3

m = 3 so we get a slope of 3

choice d is the other answer