The diagram shows a 5 cm x 5 cm x 5 cm cube.
Calculate the length of the diagonal AB.
Give your answer correct to 1 decimal place.

The diagram shows a 5 cm x 5 cm x 5 cm cubeCalculate the length of the diagonal ABGive your answer correct to 1 decimal place class=

Respuesta :

Answer:

8.7 cm

Step-by-step explanation:

The question is a 2-two-step Pythagoras theorem. (c^2 = a^2 + b^2)

Consider as such, If I were to draw a diagonal line along the base of the cube what is the length of the diagonal line. To find out that we use the theorem. We can substitute a for 5 and b for 5 as well. So

a^2 +b^2 = c^2

5^2 + 5^2 = c^2

25 + 25 = c^2

√50 = c

Then since the line side of the cube is on a 3d angle we need to do the same process again but now using the imaginary diagonal line that we just calculated and the height (5).

a^2 +b^2 = c^2

√50^2 + 5^2 = c^2

50 + 25 = c^2

√75 = c

c = 8.6602...

when rounded to 1 d.p.

c = 8.7

Line AB is 8.7 cm long.