2a=3b
4X/(4a+3b)-X/(a+b)=75
You asked:
Solve the system of equations:\[\begin{aligned}2 a &= 3 b\\\frac{4 X}{4 a + 3 b} - \frac{X}{a + b} &= 75\end{aligned}\]
MathBot Answer:
The system of equations has infinitely many solutions.
$$\begin{aligned}X &= \frac{3375 b}{2}\\a &= \frac{3 b}{2}\end{aligned}$$\(b\) is a free variable.