Answer:
X = 10
Step-by-step explanation:
if we say 1/2 base = <em>a</em>
a² = 13² - 12²
a² = 25
a = √25
a = 5
if 1/2 base = 5 then x = a × 2
hence X = 5 × 2 = 10
the correct answer would be b)8.2
f(x)= (-4)/(5-X)