Factor completely 9x2 + 42x + 49.

(3x + 7)(3x − 7)
(9x − 7)(9x − 7)
(3x + 7)(3x + 7)
(9x + 7)(9x + 7)

Tim's phone service charges $23.06 plus an additional $0.22 for each text message sent per month. if tim's phone bill was $28.56, which equation could be used to find how many text messages, x, tim sent last month?

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).

Evaluate cos2θ for cosθ = square root of 3/2