I am pretty sure that B is the answer
<span>SAS
You've been given that AC = BC. So that's the first side or S of the proof. Then you've been given â 3 = â 4, which is the angle. And finally, CM = CM, which is the second S. So you have AC=BC, and â 3 = â 4, and finally CM = CM. So SAS can be used to prove that triangle ACM is congruent to triangle BCM.</span>
Answer:
see below
Step-by-step explanation:
butterfly = x minutes
breast = y minutes
total is 50 minutes
breast stroke = butterfly +20
Part A
x+y = 50
y = x+20
Part B
Substitute the second equation into the first
x+ (x+20) = 50
2x+20 = 50
2x+20-20 = 50-20
2x = 30
2x/2 = 30/2
x = 15
y = x+20
y = 20+15
y = 35 minutes
35 minutes on the breast stroke
Part C
45 minutes on the butterfly is not reasonable
We only have a total of 50 minutes
50-45 = 5
But he spend more time on the breast stroke ( 20 minutes more), but if he spend 45 minutes on the butterfly, he would have to spend less on the breast stroke.
Answer: it will take him 4.5 hours to cover same distance
Step-by-step explanation:
Marathon runner covered the whole distance in 4 hours running at a constant speed of 8.1 km per hour.
Speed = distance / time
Distance = speed×time
Therefore, distance covered by the marathon runner in in 4 hours, running at a speed of 8.1 km per hour is
8.1 × 4 = 32.4 kilometers
if he decreased the speed to 7.2 km per hour, the distance remains 32.4 kilometers. Therefore,
At 7.2 km per hour, the time it would take him to cover the same distance would be
Distance/ speed = 32.4/7.2 = 4.5 hours
