We are given the expression (y5x2)−2. First, we can use the property that (ba)n=bnan. So, (y5x2)−2=y−2(5x2)−2. Next, we can use the property that (ab)n=anbn. So, (5x2)−2=5−2(x2)−2. Also, we can use the property that (am)n=amn. So, (x2)−2=x2∗(−2)=x−4. Therefore, (5x2)−2=5−2x−4. Substituting this back into our expression, we have:
y−2(5x2)−2=y−25−2x−4. To express with positive exponents, we can use the property that a−n=an1. So, 5−2=521=251, x−4=x41, and y−2=y21. Therefore, y−21=y2. So our expression becomes:
y−25−2x−4=y21521⋅x41=y2125x41=25x41⋅1y2=25x4y2.