Answer: 1 hour
Step-by-step explanation:
Let the distance they walked be
in time
and the distance they walked be
in time
,then
Walking speed=

Riding speed=

Also the total time taken=3 hours
∴
...(1)
Since the total distance= 20 km
∴![d_1+d_2=20\\\Rightarrow4t_1+12t_2=20\\\Rightarrow4t_1+12(3-t_1)=20..............[\text{from (1)}]\\\Rightarrow4t_1+36-12t_1=20\\\Rightarrow-8t_1=-8\\\Rightarrow\ t_1=1](https://tex.z-dn.net/?f=d_1%2Bd_2%3D20%5C%5C%5CRightarrow4t_1%2B12t_2%3D20%5C%5C%5CRightarrow4t_1%2B12%283-t_1%29%3D20..............%5B%5Ctext%7Bfrom%20%281%29%7D%5D%5C%5C%5CRightarrow4t_1%2B36-12t_1%3D20%5C%5C%5CRightarrow-8t_1%3D-8%5C%5C%5CRightarrow%5C%20t_1%3D1)
Thus, the they spent 1 hour time in walking.
Answer:
DONDODA
Step-by-step explanation:
Answer:
y = -6
Step-by-step explanation:
To simplify this equation as much as possible, we have to get the variable y by itself.
To do this, we would do the inverse operation of subtraction and add 7 to the left and right side of the equation.
-7 + 7 + 5y = -37 + 7
The 7s cancel out on the left side because -7+7 = 0 and so we are left with,
5y = -30
Then we would do the inverse operation of multiplication and divide by 5 on the left and right side of the equation.
5y/5 = -30/5
y = -6
Answer:
Use pythagorean theorem.
Step-by-step explanation:
The length of the shorter sides are 1 & 4
1^2+4^2=c^2
1+16=c^2
17=c^2
So, the length, rounded to the nearest whole inch, would be 4.
To find the perimeter, you need to find the side lengths first.
The short sides are 6 & 7.
6^2+7^2=c^2
36+49=c^2
85=c^2
So the length for that would be 8, in the nearest whole number.
Add all of the side lengths together.
6+7+8= 21
The perimeter is 21.