Lucia tried to solve the system below. Lucia’s Work

What error did Lucia make?
When Lucia solved the second equation for x, she subtracted 2y from both sides.
When Lucia solved for the value of y, she treated –2y as 2y.
When Lucia solved for the value of x, she added 18 to both sides.
When Lucia solved the second equation for x, she treated –2(–9) as 18 instead of –18.

Anna is constructing a line segment that is congruent to another segment ab. for the construction, which tool should be used to mesure segment ab

An annual marathon covers a route that has a distance of approximately 26 miles. winning times for this marathon are all over 2 hours. the following data are the minutes over 2 hours for the winning male runners over two periods of 20 years each. earlier period 14 12 15 22 13 10 19 13 9 14 20 18 16 20 23 12 18 17 6 13 recent period 7 11 7 14 8 9 11 14 8 7 9 8 7 9 9 9 9 8 10 8 (a) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the earlier period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks. for more details, view how to split a stem.) minutes beyond 2 hours earlier period 0 1 2 (b) make a stem-and-leaf display for the minutes over 2 hours of the winning times for the recent period. use two lines per stem. (use the tens digit as the stem and the ones digit as the leaf. enter none in any unused answer blanks.) minutes beyond 2 hours recent period (c) compare the two distributions. how many times under 15 minutes are in each distribution

Ineed to find the answer to number 2