Question

What's the length of side AB in ∆ABC shown?
A. 5
B. √313
C. 6
D. √15​

Answer 1

Answer:

The value of x = 5 units.

Step-by-step explanation:

Given the right-angled triangle ∆ABC with the following dimensions

AC = a = 12

BC = c = hypotenuse = 13

AB = b = x

Pythagorean Theorem

For a right-angled triangle with the sides, a and b the hypotenuse c is defined as:

$c=\sqrt{a^2+b^2}$

Thus, using the Pythagorean Theorem to determine the value 'x',

$b=\sqrt{c^2-a^2}$

as b = x, so

$x=\sqrt{c^2-a^2}$

• a = 12

• c = 13

so

$x=\sqrt{13^2-12^2}$

$x=5$

Therefore, the value of x = 5 units.