Hope you won't be turned off by a correction, but we really need to use the symbol " ^ " to denote exponentiation.
Thus, we have x^2 = 100
Taking the square root of both sides, we get x = plus or minus 10. Verify, please, that both x = -10 and x = +10 satisfy the given equation.
1-(1/5)= 4/5 or 28/35 if you multiply top and bottom by 5
Answer: 5300000
Step-by-step explanation: 7 is closer to ten so it is rounded up