Answer:
The ratio between won and lost is 
Step-by-step explanation:
<u><em>The question in English is</em></u>
A table tennis team won 21 games and lost 12 games, what is the ratio between won and lost?
Let
x ------> the number of games won
y -----> the number of games lost
we have


we know that
To find the ratio divide the number of games won by the number of games lost
so

substitute the values

Simplify

Your domain is all positive numbers, and your range is all numbers. this is because no matter what you plug in for y, x will only ever get extremely close to 0, but never reach it or go below it, and if you put in large values of y x will get very big.
Answer:

Step-by-step explanation:
A road is perpendicular to a highway leading to a farmhouse d miles away.
An automobile passes through the point of intersection with a constant speed
= r mph
Let x be the distance of automobile from the point of intersection and distance between the automobile and farmhouse is 'h' miles.
Then by Pythagoras theorem,
h² = d² + x²
By taking derivative on both the sides of the equation,




When automobile is 30 miles past the intersection,
For x = 30

Since 
Therefore,


Answer:
y = -8
Step-by-step explanation:
The domain is the x values so x=-3
y = x-5
Substituting x=-3
y = -3-5
y=-8