Please help me with this

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).

Ten times the square of a non-zero number is eqaul to ninety times the number

What statement is true? 2x^2-9x+2=-1