What is the domain of the function?

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

1. are the corresponding angles congruent 2. find the ratios of the corresponding sides 3. is triangle jkl congruent to triangle rst? if so what is the scale factor

Tim's phone service charges $26.39 plus an additional $0.21 for each text message sent per month. if tim's phone bill was $31.64, which equation could be used to find how many text messages, x, tim sent last month?