Let m and j be the current ages of Matthew and Jenny, respectively.
Now, Matthew is 3 times as old as Jenny, so the variables are in the following relation:
In 7 years, both of them will be 7 years older, i.e. their ages will be m+7 and j+7, and Matthew will be twice as old:
Now, remembering that m=3j, we can rewrite the second equation as
So, Jenny is 7 and Matthew is 21 (he's 3 times older).
In fact, in 7 years, they will be 14 and 28, and Matthew will be twice as old.
The plane will make an angle with the runway.
Explanation:
Given that the plane is flying at an altitude of 11 miles and is 193 miles from the runway, as measured from the ground.
We need to determine the angle that the plane will make with the runway.
From the given measurements, we can see that it is a right angled triangle. Hence, let us use the tangent formula to determine the angle.
The formula for the tangent is given by
Where and
Substituting these values in the above equation, we get,
Dividing, we get,
Taking on both sides of the equation, we get,
Simplifying, we have,
Hence, the angle that the plane will make with the runway is