国际学校八年级数学试卷

Choose(30’)

1)Whichgraphrepresentthelinearfunction？()

A.B.C.D.

2)Atafactory,thecostofmakingdifferentnumbersoftoothbrushesisshowninthetablebelow.()

Alinearfunctionmodelsthecostbasedonthenumberoftoothbrushesmade.Whichstatementabouttherateofchangeofthisfunctionistrue?

A.Thecostincreasesby$1.50foreachadditionaltoothbrushmade.

B.Thecostincreasesby$4.50foreachadditionaltoothbrushmade.

C.Thecostincreasesby$9.00foreachadditional3toothbrushesmade.

D.Thecostincreasesby$18.00foreachadditional3toothbrushesmade

3)Whatisanexpression?()

A.Aformulawithanequalssign.B.Aformulawithaplussign.

C.Aformulawithoutaplussign.D.Aformulawithoutanequalssign.

4)TriangleAandtriangleBaregraphedonthecoordinateplanebelow.WhichsequenceoftransformationswillmaptriangleAontoitscongruentimage,triangleB?()

A.areflectionoverthe-axis,thenareflectionoverthe-axis

B.atranslationunitsdown,thenareflectionoverthe-axis

C.areflectionoverthe-axis,thenatranslationunitstotheleft

D.arotationclockwiseabouttheorigin,thenatranslationunitstotheleft

5)Whichstatementbestdescribesthedatainascatterplotwherethey-valuesaredecreasingasthex-valuesareincreasing?()

A.Thedatacanbestbemodeledbyaverticalline.

B.Thedatacanbestbemodeledbyahorizontalline.

C.Thedatacanbestbemodeledbyalinewithapositiveslope.

D.Thedatacanbestbemodeledbyalinewithanegativeslope.

6)Whichsetoforderedpairsdoesnotrepresentafunction?()

A.{(1,10),(3,18),(5,26),(7,34),(9,24)}B.{(2,10),(3,20),(4,15),(5,5),(6,25)}

C.{(0,8),(5,4),(10,0),(15,4),(20,8)}D.{(9,1),(6,2),(3,3),(6,4),(9,5)}

7)Usingthefactoringmethod,solvethequadraticequation:x2+4x+4=0()

A.0and1B.1and2C.2D.-2

8)Theperimeterandareaofarectangularparkare80mand400m2.Whatisitslength?()

A.20mB.15mC.30mD.40m

9)FindtheperfectCvaluesothatthetrinomialcanbeexpressedasthesquareofabinomial?()

X2-12X+C

A.36B.-36C.144D.-144

10)Ifoneoftherootsofthequadraticequationx2+mx+24=0is1.5,thenwhatisthevalueofm?()

A.-22.5B.16C.-10.5D.-17.5

11)Whenaretherootsofaquadraticequationrealandequal?()

A)Whenthediscriminantispositive.B)Whenthediscriminantiszero.

C)Whenthediscriminantisnegative.D)Whenthediscriminantisnon-negative

12)Thesidesoftwosquareplotsare(2x−1)mand(5x+4)m.Theareaofthesecondsquareplotis9timestheareaofthefirstsquareplot.Findthesideofthelargerplot.()

A)15mB)13mC)31mD)39m

13)Whatisthenatureoftherootsofthequadraticequation25x2−49=0?

A)RealanddistinctB)RealandequalC)IrrationalD)Norealroots

14)Whichbestdescribesaquadraticequation?()

A.Anequationthathassomethingraisedtothesecondpower.

B.Anequationthathas2xasoneofit'sterms.

C.Anequationthathasnopowerthatisgreaterthan2.

D.Anequationwherexisraisedtothesecondpowerandthatisthehighestpoweronx.

15)Thefunctiony=-16t2-248modelstheheightyinfeetofastonetsecondsafteritisdroppedfromtheedgeofaverticalcliff.Howlongwillittakethestonetohittheground?Roundtothenearesthundredthofasecond.()

A.7.87secondsB.3.94secondsC.0.25secondsD.5.57seconds

Translation：(12’)

Slope:________________Coordinate:____________Intercept:_______________

Equation:_______________Root:________________Solve:_______________

Graph:______________Line:___________________Function:_______________

Coeffient:_________Constant：_____________Perfectsquare：______________

FindtheperfectCvaluetocompleteeachstatementasthesquareofabinomial.(8’)

Solvethefollowingequation：(18’)

Thewidthofarectangleis1mlessthantwicethelength.Iftheareaoftherectangleis100m2whatarethedimensionsoftherectangle?

(6’)

Twocarsstartoutatthesamespot.Onecarstartstodrivenorthat40mphand3hourslaterthesecondcarstartsdrivingtotheeastat60mph.Howlongafterthefirstcarstartsdrivingdoesittakeforthetwocarstobe500milesapart?

(6’)

Twopeoplecanpaintahousein14hours.Workingindividuallyoneofthepeopletakes2hoursmorethanittakestheotherpersontopaintthehouse.Howlongwouldittakeeachpersonworkingindividuallytopaintthehouse?

(7’)

*ExtraQuestions：(15’)

1、Thewholenumbersfrom1to7aretobeplacedinthesevencirclesinthediagram.Ineachofthethreetrianglesdrawn,thesumofthethreenumbersisthesame.Twoofthenumbersaregiven.Wh