题目

将方程配方后，原方程变形为（ ）A. B. C. D. 答案：【答案】A【解析】把常数项3移项后，应该在左右两边同时加上一次项系数4的一半的平方．移项得,x2+4x=−3，配方得,x2+4x+4=−3+4，即(x+2)2=1.故答案选A. 阅读理解 　　Jeanette Rankin was born on a ranch in Montana, USA in 1882．In those days, Montana was still a frontier state, and life there was hard．Men and women shared the difficult outdoor work．But young Jeanette noticed men and women were not equal in many ways．For instance, at election time, women were not allowed to vote．Jeanette thought this was not fair, and several years later, after graduating from college, she realized how to help change the situation． 　　First, she joined with other women．and gave speeches through the state．Thanks to their years of efforts, Montana women were finally allowed to vote．This experience changed Jeanette's life．She wanted do work for the welfare of women and children everywhere．She was now well-known throughout Montana, so she decided to run for the US Congress．In 1916, she became the first woman in the Congress of the United Staters． 　　Just six days after Rankin first attended Congress in 1917, American President Wilson called for a vote to go to war against Germany, as German submarines(潜水艇)attacked American ships during World War I．When Jeanette was called upon to vote, she said,“I want to stand by my country, buy I cannot vote for war．I vote no．”Forty-nine other congress members also voted no, but she was the person who was criticized most．Newspapers said her decision came from weakness and she was anti-American． 　　In the Second World War, Japanese warplanes attacked the American base at Pearl Harbor in 1941．The time came again for the US Congress members to vote for or against going to war．Everyone was waiting for Jeanette Rankin to vote, who rose and said,“As a woman, I can't go to war, so I refuse to send anyone else”．Out of 471 members, she was the only member who voted against war．After that, she received thousands of letters．Most people criticized her, but some praised her for her courage． 　　Shortly before she died in 1973, she was asked if she regretted voting “no”to the two wars．“Never,”she answered．“If you are against war, you're against war regard less of what happens．” 　　Today, in the US Congress Building, there is a statue of Jeanette Rankin．On the base of the statue are her words：“I cannot vote for war．” (1) When Jeanette Rankin was young, ________． [　　] A． women were not allowed to work with men B． women had no right to vote C． women could not go to college D． women could not deliver speeches in public (2) She decided to run for the US Congress because ________． [　　] A． She wanted to become famous throughout the USA B． She hated was C． She wanted to help more women and children D． She was a born politician (3) Which is true according to the passage? [　　] A． Jeannette was the only member to vote no to the two wars． B． Jeannette voted no to the wars because she was weak． C． Everyone in the USA hated her when she voted no to the war against Japan． D． Jeanette believed that no war was right． (4) From the passage we can tell that Jeanette Rankin was ________． [　　] A． full of courage B． Very fair C． Very intelligent D． very stubborn． (5) The American people remember Jeanette Rankin mainly for ________． [　　] A． her fighting for women's rights B． her being the first American woman Congress member C． her fighting against war D． her efforts to help women get the voting right