solve for r

There is a right triangle with the hypotenuse as r , the angle as 45 degrees and opposite side as 20.

I am having a hard time finding this out. I had tan 45 = 1.61 20(1.61) = 32.4 but this is wrong.

A basic rule for right triangles is sine(theta) = opposite/hypotenuse

20 = your opposite side
theta is your angle

rearrange to fit your problem:
hypotenuse = opposite/sin(theta)
plug in and solve
make sure your calculator is in degrees, not radians too.

what you did wrong was this:

tan(theta) = opposite / adjacent

An easy trick to remember is SOHCAHTOA (pronounced so-ka-toe-a):

sin (S) is opposite(O)/hypotenuse(H)
cos (C) is adjacent (A)/hypotenuse(H)
tan (T) is opposite (O)/adjacent (A)

I'm in college calculus now, and I still use that trick to remember.

To solve for the value of r in the given right triangle, you can use the sine function. Given that the opposite side is 20 and the angle is 45 degrees, we can write the equation as:

sin(45 degrees) = opposite / hypotenuse

Substituting the known values:

sin(45 degrees) = 20 / r

Now, to isolate r, we can rearrange the equation:

r * sin(45 degrees) = 20

To find the value of r, we need to evaluate the sin(45 degrees). The sine of 45 degrees is equal to 1 / √2, which is approximately 0.707.

Plugging in this value:

r * 0.707 = 20

Now, divide both sides of the equation by 0.707:

r = 20 / 0.707

Evaluating this expression:

r ≈ 28.28

Therefore, the value of r in the given right triangle is approximately 28.28.