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:
sorry I don't know the answer
You want to solve for x so add 18 from both sides of the equal sign. making it 3x=12. then divide both sides by 3 making x=4. x is 4.
I also need this answer so when you find out let me know