Answer:
x=12
Explanation:
The right side is a right triangle
The base is 1/2 of the bottom or 5
The height is x and the hypotenuse is 13
We can use the Pythagorean theorem
a^2 +b^2 = c^2
5^2 +x^2=13^2
25+x^2 = 169
Subtract 25 from each side
25-25+x^2 = 169-26
x^2 =144
Take the square root of each side
sqrt(x^2) = sqrt(144)
x= 12