Translate twice x is 5 into a mathematical expression

Each month, a shopkeeper spends 5x + 14 dollars on rent and electricity. if he spends 3x−5 dollars on rent, how much does he spend on electricity? for which value(s) of x is the amount the shopkeeper spends on electricity less than $100? explain how you found the value(s).

What is the circumference of a circle with an area of 50.24 cm²?

When is g(x) = 0 for the function g(x) = 5.23x + 4?