Nancy sold half of her books and then bought 7 more she now has nine books how many books did she begin with

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).

Write a function for a rotation 90 degrees counter clockwise about the origin, point 0

Ineed with math stuff it involves graphs