What's the length of side AB in ∆ABC shown?
A. 5
B. √313
C. 6
D. √15
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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:
[tex]c=\sqrt{a^2+b^2}[/tex]
Thus, using the Pythagorean Theorem to determine the value 'x',
[tex]b=\sqrt{c^2-a^2}[/tex]
as b = x, so
[tex]x=\sqrt{c^2-a^2}[/tex]
so
[tex]x=\sqrt{13^2-12^2}[/tex]
[tex]x=5[/tex]
Therefore, the value of x = 5 units.