Question

A river flows at 2m/s the velocity of a ferry relative to the shore is 4m/s at right angles to the current what is the velocity of the ferry relative to the current?

Answer 1

x is downstream
y is across
x velocity = -2
y velocity = 4

tan T = -2/4
T = 26.6 degrees from straight across
or 90-26.6 = 63.4 from straight upstream
magnitude = sqrt(4+16) = 2 sqrt 5 = 4.5

Answer 2

write the equation of each ellipse describe below , c(0,0);a=6,b=4; horizontal major axis

Answer 3

Since the origin is zero. The formula will be x²/a² + y²/b²=1(a is the denominator of x because the major axis is horizontal)
Therefore
x²/6² + y²/3² =1
=x²/36 + y²/9 =1 is the equation of the ellipse