Determine if the given information would form unique, many different triangles, or no triangle. 9 inches, 7 inches, 18inches

Find the sum of 4x^{2} -4+6 and -7^{2} +3x+1

2people are trying different phones to see which one has the better talk time. chatlong has an average of 18 hours with a standard deviation of 2 hours and talk-a-lot has an average of 20 hours with a standard deviation of 3. the two people who tested their phones both got 20 hours of use on their phones. for the z-scores i got 1 for the chatlong company and 0 for talk-a-lot. what is the percentile for each z-score?

Combine like terms to make a simpler expression 3z+z