Answer:
20cm
Step-by-step explanation:
for the triangle:
Perimeter = 30cm
a + a + a = 30
3a = 30
hence a = 10cm
For the rectangle:
Perimeter = 30cm
a + a + b + b = 30
but a = 10cm
10 + 10 + b + b = 30
20 + 2b = 30
2b = 10
hence b = 5cm
Perimeter of square = b + b + b + b
= 5 + 5 + 5 + 5 = 20cm
The answer adds up to 103
Answer:
(x,y) (9,4)
Step-by-step explanation:
-2x+7y = 10
x -3y = -3 (move x to the other side)
-2x +7y = 10
x = -3 + 3y (put in for x)
-2 (-3 +3y) +7y =10 ( slove for y)
6-6y +7y = 10
6+y = 10
y = 10-6
y = 4
go back slove for x
x = -3+3x4
x = 9
It's hard to tell from the way the question is written.
-- If he has 5 pennies, then it doesn't matter how many he lost.
He has five of them.
-- If he has 5 pennies after he lost three of them, then there are
eight now, just like there were before, but he only has 5 of them.
-- If he had 5 pennies before he lost three, then there are still
5 pennies, but he only has two of them.
Answer:
5 hours 12 seconds
Step-by-step explanation:
For the entire train to pass the person, the head of the lead wagon must travel (9·16 m) in 12 seconds. It is traveling at a speed of ...
(9·16 m)/(12 s) = (144/12) m/s = 12 m/s
For the train to travel 216 km + 144 m = 216,144 m will take ...
(216,144 m)/(12 m/s) = 18,012 s = 5 hours 12 seconds
_____
<em>Comment on the speed</em>
The speed of this "wagon train" is about 26.8 miles per hour, faster than any human and most animals can run for long periods. The Pony Express cross-country mail delivery service maybe set a reasonable standard for cross-country travel. Its average speed was about 10 miles per hour.