One equation in a system isy = 2x - 4. Which equation gives the system no solution? y = 2x - 4

y = -2x + 4

y = 2x + 9

y = 14x - 4

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?

Gabrielle's age is two times mikhail's age. the sum of their ages is 84. what is mikhail's age?

Simplify the algebraic expression 8y-2(y+4)