Please help with this rectangle figure

15.53 sq inches, 15.71 inches

Step-by-step explanation:

(3 * 4) + (1.5^2 * pi)/2 = 12 + 3.53 = 15.53 sq inches

3 + 4 + 4 + (2pi * 1.5)/2 = 15.71 inches

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4