3. Fred bought an LCD TV 12 inches long. The diagonal of the LCD TV measures 20 inches. Find the width of of the tv

16 inches

Step-by-step explanation:

To solve this question, we will use the Pythagoras theorem which will be:

Diagonal² = Length² + Width²

20² = 12² + width²

400 = 144 + width²

width² = 400 - 144

Width² = 256

Width = ✓256

Width = 16

The width of the tv is 16 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