首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
If, which of the following could be the value of y ?
If, which of the following could be the value of y ?
admin
2014-08-13
72
问题
If
, which of the following could be the value of y ?
选项
A、4
B、1
C、-1
D、-3
E、-5
答案
D
解析
One approach to answer the question is to solve the equation for y as follows.
2(2y-3)=y(3-y)
4y - 6 = 3y - y
2
y
2
+y -6 = 0
(y + 3)(y-2)= 0
Since a product equals 0 only if at least one of the factors equals 0,
y + 3 = 0 or y - 2 = 0
y = -3 or y = 2
Thus, there are two values of y that satisfy the equation, —3 and 2. The value -3 is Choice D, and the value 2 is not among the answer choices. The correct answer is Choice D.
Another approach is to determine, for each answer choice, whether the equation holds. To do this, you can substitute the answer choice for y in the equation
, replace the equals sign in the equation by the place-holder symbol
, and then simplify to see whether the two expressions are in fact equal.
For Choice A, substituting y = 4 in the equation
and replacing the equals sign = with the placeholder symbol
yields the relationship
, which can be simplified as follows.
Since
, you can conclude that the placeholder symbol does not represent equality, and therefore the equation does not hold for y = 4.
If you continue evaluating the answer choices, you will find that the correct answer is Choice D, -3. To see that the equation
is true when y = -3, substitute y = -3 in the equation and replace the equals sign = with the placeholder symbol
. This yields the relationship
. This relationship can be simplified as follows.
Since 3 = 3, you can conclude that the placeholder symbol represents equality, and therefore the equation holds for y = -3. The correct answer is Choice D.
转载请注明原文地址:https://kaotiyun.com/show/j5kO777K
本试题收录于:
GRE QUANTITATIVE题库GRE分类
0
GRE QUANTITATIVE
GRE
相关试题推荐
Somepeoplethinkoflifeasagame.Therearesimilaritiesbetweenlifeandgames;bothcanbeplayed,bothhaverules,andbot
WhenIwasyoung,Ispentmysummervacationsonmygrandparents’farm.ThesummerthatIgraduatedfromcollege,I【C1】______my
Bytheyear2020,China’spopulationprobably________1.4billion.
Thevitaminsnecessaryforahealthybodyarenormallysuppliedbyagoodmixeddiet(饮食),includingavarietyoffruitsandgre
Robertlookedasifhewereaboutto______whenhismotiveswerequestioned.
Thesecourses,ifproperlyconducted,will______themindsofthestudents.
NocountryintheworldhasmoredailynewspapersthantheUSA.Therearealmost2,000ofthem,ascomparedwith180inJapan,
Thefollowingdatasufficiencyproblemsconsistofaquestionandtwostatements,labeled(1)and(2),inwhichcertaindataare
Solvetheproblemandindicatethebestoftheanswerchoicesgiven.NUMBERS:Allnumbersusedarerealnumbers.FIGURES:
Inthefigureabove,whatistheperimeterof△PQF?(1)ThelengthofsegmentPTis2.(2)ThelengthofsegmentRSis.
随机试题
阅读材料并回答问题:如何以更好的质量实现经济社会的发展,是我们面临的也是必须要解决好的重大问题。在未来的发展中,资源环境对经济发展已构成严重制约,城乡之间、区域之间、经济与社会之间发展不平衡的矛盾趋于突出,资源相对短期、生态环境脆弱、环境容量不足
mRNA剪接过程中被去除的部分叫做
某猪场2岁种公猪,精神沉郁,步态强拘,拱背,腰部触诊敏感,常做排尿姿势。尿检可见红细胞、白细胞、盐类结晶、肾上皮细胞,该病可能的诊断是()
A.桂枝茯苓丸B.香棱丸C.启宫丸D.开郁种玉汤E.开郁二陈汤
甲河是多国河流,乙河是国际河流。根据国际法相关规则,下列哪些选项是正确的?(2011—卷一—74,多)
根据《建筑工程施工质量验收统一标准》GB50300—2013,建筑工程质量验收的最小单元是()。
根据《中华人民共和国村民委员会组织法》,村务监督委员会成员的产生方式是()。
案例下面是某求助者的WAIS-RC测验结果:根据以上测验得分,可以判断该求助者()
Manythingsmakepeoplethinkartistsareweird.Buttheweirdestmaybethis:artists’onlyjobistoexploreemotions,andyet
Yearsaftertheeconomicrecessionwitnessed_________businessrecoverythroughoutthewholenation.
最新回复
(
0
)