Question

In centimeters, what is the unknown length in this right triangle?

Answer 1

The work out the length of the missing side you need to use Pythagoras' theorem which states that the sum of the squares of the two sides, in this case x and 60, is equal to the sum of the square of the hypotenuse. This can be formulated as $a^{2} +b^{2}=c^{2}$. In this case x can replace a or b (I've replaced a).
$x^{2} +b^{2}=c^{2}$ 
To solve for x rearrange the equation by subtracting $b^{2}$ from both sides:
$c^{2} -b^{2}=x^{2}$
Substitute the numbers in:
$x^{2} = 61^{2} -60^{2}$ 
                 = 3721-3600
                 = 121
Take the square root of 121 to find x:
x =$\sqrt{121}$
   = 11cm 

Answer 2

Answer:

11

Explanation:

Using the Pythagorean Theorem,

a² + b² = c² is the same as c² - b² = a²

c = 61

61^2 =  61 X 61 = 3,721  

b = 60

60^2 = 60 X 60 =  3,600  

Next, we subtract:

3,721 - 3,600 = 121  

√121 = 11

(x = 11 cm)

so 11 is your answer