The work of a student to solve a set of equations is shown:

equation a: y = 4 − 2z
equation b: 4y = 2 − 4z

step 1: −4(y) = −4(4 − 2z) [equation a is multiplied by −4.]
4y = 2 − 4z [equation b]
step 2: −4y = 4 − 2z [equation a in step 1 is simplified.]
4y = 2 − 4z [equation b]
step 3: 0 = 6 − 6z [equations in step 2 are added.]
step 4: 6z = 6
step 5: z = 1

in which step did the student first make an error?
step 1
step 3
step 4
step 2

Which simplifys to a+ b? a-(1-b)+1 -(1-a)-b+1 (a--1) -1)+1

For the quadratic function [tex]y=(x+4)^2-1[/tex] , do the following: a) rewrite the function in the standard form, b) rewrite the function in intercept form, c) find the vertex, d) find the y-intercept, e) find the x-intercepts.

Name and describe the three most important measures of central tendency. choose the correct answer below. a. the mean, sample size, and mode are the most important measures of central tendency. the mean of a data set is the sum of the observations divided by the middle value in its ordered list. the sample size of a data set is the number of observations. the mode of a data set is its highest value in its ordered list. b. the sample size, median, and mode are the most important measures of central tendency. the sample size of a data set is the difference between the highest value and lowest value in its ordered list. the median of a data set is its most frequently occurring value. the mode of a data set is sum of the observations divided by the number of observations. c. the mean, median, and mode are the most important measures of central tendency. the mean of a data set is the product of the observations divided by the number of observations. the median of a data set is the lowest value in its ordered list. the mode of a data set is its least frequently occurring value. d. the mean, median, and mode are the most important measures of central tendency. the mean of a data set is its arithmetic average. the median of a data set is the middle value in its ordered list. the mode of a data set is its most frequently occurring value.