The work of a student to solve a set of equations is shown below: equation 1: x + 2y = 10 equation 2: 2x + 5y = 15 step 1: −2(x + 2y) = −2(10) 2x + 5y = 15 step 2: −2x − 4y = −10 2x + 5y = 15 step 3: 1y = 5 step 4: x + 2(1) = 10 step 5: x = 8 in which step did the student first make an error?

The mean of a set of data is -3.82 and its standard deviation is 2.31. find the z score for a value of 3.99.

In the following situation, determine whether you are asked to determine the number of permutations or combinations. then do the calculation how many ways are there to pick a starting five from a basketball team of twelve members? a. permutation; ps - 2520 b. combination; 1c, - 792 c. combination: 2cs - 2520 d. permutation; ps - 95040

Given the points a(-2, 1) and b(8, 6), find the coordinates of the point c on directed line segment ab, that partitions ab in the ration 2: 3.