Answer:
After simplifying we get (x,y) as (1,3).
Step-by-step explanation:
Given:
,
![x-7y=-17](https://tex.z-dn.net/?f=x-7y%3D-17)
We need to use elimination method to solve the and simplify the equations.
Solution;
Let
⇒ equation 1
Also Let
⇒ equation 2
Now by solving the equation we get;
first we will Add equation 2 from equation 1 we get;
![(x+7y)+(4x-7y)=22+(-17)\\\\x+7y+4x-7y=22-17\\\\5x=5](https://tex.z-dn.net/?f=%28x%2B7y%29%2B%284x-7y%29%3D22%2B%28-17%29%5C%5C%5C%5Cx%2B7y%2B4x-7y%3D22-17%5C%5C%5C%5C5x%3D5)
Now Dividing both side by 5 using division property of equality we get;
![\frac{5x}{5}=\frac{5}{5}\\\\x=1](https://tex.z-dn.net/?f=%5Cfrac%7B5x%7D%7B5%7D%3D%5Cfrac%7B5%7D%7B5%7D%5C%5C%5C%5Cx%3D1)
Now Substituting the vale of x in equation 1 we get;
![x+7y=22\\\\1+7y=22](https://tex.z-dn.net/?f=x%2B7y%3D22%5C%5C%5C%5C1%2B7y%3D22)
subtracting both side by 1 using subtraction property of equality we get;
![1+7y-1=22-1\\\\7y=21](https://tex.z-dn.net/?f=1%2B7y-1%3D22-1%5C%5C%5C%5C7y%3D21)
Now Dividing both side by 7 using division property of equality we get;
![\frac{7y}{7}=\frac{21}{7}\\\\y=3](https://tex.z-dn.net/?f=%5Cfrac%7B7y%7D%7B7%7D%3D%5Cfrac%7B21%7D%7B7%7D%5C%5C%5C%5Cy%3D3)
Hence we can say that, After simplifying we get (x,y) as (1,3).
Answer:
Option B.
Step-by-step explanation:
We need to express 505 kL in L.
Here, kL means kiloliter and L means liter.
We know that
1 kL = 1000 L
Using this conversion we can easily convert 505 kL in L.
Multiply both sides by 505.
505 × 1 kL = 505 × 1000 L
505 kL = 505,000 L
The value of 505 kL can be expressed as 505,000 L.
Therefore, the correct option is B.
To solve this problem, let us first assign some variables.
Let us say that:
v1 = velocity of airplane = 180 mph
t1 = time travelled by airplane
v2 = velocity of jet = 330 mph
t2 = time travelled by jet
Since we know that distance is the product of velocity and
time, and that the distance travelled by the two must be equal for the jet to
catch up to the plane, hence:
v1 * t1 = v2 * t2
But we know that:
t1 = t2 + 1
Therefore:
180 (t2 + 1) = 330 t2
180 t2 + 180 = 330 t2
150 t2 = 180
t2 = 1.2 hours
<span>Therefore the jet can catch up to the plane after 1.2
hours it takes off.</span>