Answer:
Step-by-step explanation:
Let
x ----> the height of the top of a mountain above sea level
y ----> the deep of a shipwreck below the sea level
we know that
The sea level represent the height equal to zero
In this problem we have
---> is positive because is above sea level
---> is negative because is below sea level
To find out the distance between the mountain top and the ship wreck, determine the absolute value of the difference between the two values
substitute the values
Answer:
Step-by-step explanation:
Note that one equation has -2y and the other has +2y. The fastest solution is to add the equations together. The two terms will cancel out, eliminating the y terms.
She must have multiplied it by 5.
That would've given her:
x - y = 15
2.5x + y = 25
Now we can add them and the y-terms will eliminate each other. Because one is -y, and the other is positive y. -y + y = 0.