# Algebra

posted by on .

Two questions?

Build a patio-hypotenuese is 50 feet long
the two sides of patio are same. What is the length of one side of the patio

I think I set it up a^2 + b^2 = c^2
a^2 + b^2 = 50^2
a^2+ b^2 = 2500
then I just could say 2a^2 = 2500
a^2 = 2500/2
a^2 = 1250
sqrt of 1250 = 35.36 correct?

2nd question? Boat across a river with the current moving you downstream so the boat goes at a 30 degree angle. If the river is 400 feet across, how far downstream do you end up-this one I'm totally confused on

• Algebra - ,

first question is correct.

2nd:

drew a line straight across, called it 400 ft
then from starting point drew a line 30° from the 400 line.
got a right-angled triangle, called the distance downstream x ft

tan 30° = x/400
x = 400 tan 30°230.94

• Algebra-please recheck Reiny - ,

I'm not sure I'm understanding the x=
400 tan 30 *230.94 or would it be that it equals 230.94

• typo ! Algebra - ,

that's a typo

should have been
x = 400 tan 30°
= 230.94