Answer:
Width of screen =57.44 cm
Step-by-step explanation:
Please refer to the attached image:
The TV screen is usually in the form of a rectangle.
The diagonal of the TV is termed as the screen size.
Size is given to be 70 cm
Height = 40 cm
As per the attached image:
BC = 40 cm
BD = 70 cm
Pythagoras theorem is given as:
[tex]\text{Hypotenuse}^{2} = \text{Base}^{2} + \text{Height}^{2}[/tex]
Using pythagoras theorem in [tex]\triangle BDC[/tex]:
[tex]BD^{2}= BC^{2}+ CD^{2}[/tex]
[tex]70^{2}= 40^{2}+ CD^{2}\\\Rightarrow CD^{2} =4900 - 1600\\\Rightarrow CD^{2} =3300\\\Rightarrow CD =57.44 cm[/tex]
Hence, width of screen, CD =57.44 cm