Is segment AB tangent to circle O shown in the diagram, for AB = 8, OB = 3.75, and AO = 10.25. Explain your reasoning and show all work in your own words. (The figure is not drawn to scale.)

9514 1404 393

  not tangent

Step-by-step explanation:

AB will be tangent to circle O if AB ⊥ BO. That can be tested by checking to see if AB, BO, and AO satisfy the Pythagorean theorem.

According to the Pythagorean theorem, the length of the hypotenuse of a right triangle with legs 3.75 and 8 will be ...

  hypotenuse = √(3.75² +8²) = √78.0625 ≈ 8.835

The length of AO is somewhat greater than that, so AB cannot be a tangent to the circle.

__

The angle ABO is obtuse.

m a t h w a y. c o m

step-by-step explanation:

- "runner b is moving at a slower rate."

- "the graphs shown are graphs of distance(km) against time(min).

the slopes of this graphs are are given by:

slope = (change in y)/(change in x)

= (change in distance)/(change in time)

this is the formula for finding the speed. so, the slope of these graphs represent the speed of the runner.

taking each division in the graph to represent 1 on both axis:

runner a ⇒ speed = (2-0)/(1-0)

= 2/1

= 2 km/min

runner b ⇒ speed = (3-0)/(3-0)

= 3/3

= 1 km/min

this shows that   runner b is moving at a slower rate."