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.
Simply put, it says that the numbers can be added in any order, and you will still get the same answer. For example, if you are adding one and two together, thecommutative property<span> of addition says that you will get the same answer whether you are adding 1 + 2 or 2 + 1. This also works for more than two numbers.</span>
Answer:
The Proof is given below.
Step-by-step explanation:
Given:
LN⊥KM,
KL≅ML
To Prove:
ΔKLN≅ΔMLN
Proof:
In Δ KLN and Δ MLN
KL ≅ ML ....……….{Given i.e Hypotenuse }
LN ≅ LN …………..{Reflexive Property}
∠ LNK ≅ ∠ LNM ……….{ LN ⊥ KM i.e Measure of each angle is 90° given}
Δ KLN ≅ Δ MLN ….{By Hypotenuse Leg Theorem}
....Proved
Answer:
y=15
x=43
(any variable can be used, I used x and y to make it easier to show)
Step-by-step explanation:
x+y=58
x-y=28
get x by its self
x=58-y
then subsitute into the other equation
(58-y)-y=28
58-2y=28
-2y=-30
y=15
sub. again
x+15=58
x=43
Answer:
The vertex of this parabola, 
, can be found by completing the square.
Step-by-step explanation:
The goal is to express this parabola in its vertex form:
,
where 
, 
, and 
are constants. Once these three constants were found, it can be concluded that the vertex of this parabola is at 
.
The vertex form can be expanded to obtain:
.
Compare that expression with the given equation of this parabola. The constant term, the coefficient for 
, and the coefficient for 
should all match accordingly. That is:
.
The first equation implies that is equal to 
. Hence, replace the "
" in the second equation with 
to eliminate 
:
.
.
Similarly, replace the "" and the "" in the third equation with and 
, respectively:
.
.
Therefore, 
would be equivalent to 
. The vertex of this parabola would thus be:
.
