Answer:
24
Step-by-step explanation:
lets say x is one and y is 1. 5 times 1 is five and to the power of 2 thats 25 and minus 1 equals 24
[tex](x-5y)^2=x^2-2\cdot x\cdot5y+(5y)^2=x^2-10y+25y^2[/tex]