He perimeter of the scalene triangle is 54.6 cm. A scalene triangle where all sides are different lengths. The base of the triangle, labeled 3 a, is three times that of the shortest side, a. The other side is labeled b.

Which equation can be used to find the value of b if side a measures 8.7 cm?

54.6 - (8.7 + 3*8.7) = b

Step-by-step explanation:

we know the value of a

a = 8.7

the side '3a' is 3 times a

3*8.7 = 26.1

now the definition of perimeter is all the sides added up together :

side a +  side 3a +  side b = 54.6

8.7 + 26.1 + b = 54.6

34.8 + b = 54.6

b = 19.8

or

side a +  side 3a +  side b = 54.6

side 4a + side b = 54.6

4*8.7 + b = 54.6

- "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."