Substitution methode:
y=2x-5
4x-y=7
i thought you do it like this:
4x-2x-5=7
2x-5=7
2x=12
x=6
but that's not right.. what did i do wrong?

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?

The probability that an adult possesses a credit card is .70. a researcher selects two adults at random. by assuming the independence, the probability that the first adult possesses a credit card and the second adult does not possess a credit card is:

Which of the following represents the length of a diagonal of this trapezoid?