Update EIP-7444: Replace broken mathematic equation with images

Merged by EIP-Bot.

EIPS/eip-7444.md

@@ -58,9 +58,7 @@ Locked Assets have become increasingly popular and used in different parts of de
 
  Locked Assets cannot be valued normally since the value of these assets can be varied through time and many other different factors throughout the locking time. For instance, The Black-Scholes Model or Black-Scholes-Merton model is an example of a suitable model to estimate the theoritical value of asset with the consideration of impact of time and other potential risks. 
 
-$$ C = N(d_1)S_t - N(d_2)Ke^{-ert} $$
-
-$$ \text {where } \small d_1 = \frac{\ln\frac{S_t}{K} + (r + \frac{\sigma^2}{2})}{\sigma \sqrt t} \text{ and } d2 = d1 - \sigma \sqrt t$$
+![Black-Sholes Model](../assets/eip-7444/equation.png)
 
 - $C=\text{call option price}$
 - $N=\text{CDF of the normal distribution}$