Answer:
Do it on standard form
Step-by-step explanation:
Doing it by standard form ensures simplifying
59.4cm
Use Pythagorean theorem to find the diagonal (^ means exponent)
a^2 + b^2 = c^2
42^2 + 42^2= c^2
1764+1764=c^2
3528=c^2
square root both sides
c= 59.39696962
round and you get 59.4 cm
Answer:

Step-by-step explanation:

Your answer is 1.5 if you multiply 15 by 10% you get 1.5 and if you ivide 1.5 by 10% you get 15 so you can find your answer and check it
hope this helps have a nice day.