Verified answer

For this one you have to draw a triangle!

cosØ = 3/5 therefore if you draw a triangle with that information you will have the hypotenuse = 5 the adjacent side equal to 3 and the angle Ø between the two lines.

After drawing this right angled triangle you will see that by using Pythagorus's thereom you can find the third side

25 - 9 = c^2

16 = c^2

c = 4

Therefore you have the opposite side = 4

then using trig you know that

sinØ = 4/5.

step 2

sin2Ø expands to 2sinØcosØ

but we know sinØ = 4/5 and cosØ = 3/5

therefore the answer is 2 * 4/5 * 3/5

= 24/5