20 17 examination questions in the first chapter of the second volume of seventh grade mathematics 1. Multiple choice questions (3 points for each small question, 36 points for * * *).
1. As shown in the figure, split equally? ABC, DE∨BC, then the isometric * * * in the figure has ().
A.3 to B.4 to C.5 to D.6.
2. As shown in the figure, the straight line l 1∑L2,? 1=55? ,? 2=62? And then what? 3 is ()
.50 caliber? B.53？ C.60？ D.63？
3. As shown in the figure, it will contain 30? The right-angle vertex of a triangular plate with an angle is placed on one of two parallel lines. If? 1=35? And then what? The degree of 2 is ()
A. 10？ B.20？ C.25？ D.30？
4.(20 15? Hebei senior high school entrance examination) as shown in figure, AB∨EF, CD? EF，？ BAC=50？ And then what? Automatic Call Distributor = ()
A. 120？ B. 130？ C. 140？ D. 150？
The trademark of a commodity can be abstracted into three lines as shown in the figure, in which AB∨CD,? EAB=45？ And then what? The degree of FDC is ()
.30 caliber? B.45？ C.60？ D.75？
6. As shown in the figure, both OA and OB of AOB are flat mirrors, but? AOB=28？ There is a point p on OB. After a beam of light from point P is reflected by point Q on OA, the reflected light QR is just parallel to OB. QPB =()
.28 caliber? B.56？ C. 100？ D. 120？
7. As shown in the figure, Line A and Line B are cut by Line C. Now, the following four conditions are given:
①? 1=? 5; ②? 1=? 7; ③? 2+? 3= 180? ; ④? 4=? 7.
The serial number of the condition that can judge a∨b is ()
A.①② B.①③ C.①④ D.③④
8. As shown in the figure, AB∑CD and straight line EF are at points G, H,? AGH=60？ And then what? The degree of EHD is ()
.30 caliber? B.60？ C. 120？ D. 150？
9. If the straight line A∑B, points A and B are on the straight lines A and B respectively, and AB=2 cm, then the distance between A and B is ().
A. equal to 2 cm. B. greater than 2 cm
C. not more than 2 cm. D. not less than 2 cm
10. As shown in the figure, lines A∑b and C intersect with A and B, 1=60? And then what? 2 equals ()
.60 caliber? B.30？ C. 120？ D.50？
1 1. Fold the rectangle ABCD along EF as shown in the figure. If? 1=50? And then what? AEF is equal to ()
A. 1 10？ B. 1 15？ C. 120？ D. 130？
12. As shown in the figure △DEF translates △ABC, and points B, E, C and F are on the same straight line. If BF= 14 and CE=6, the length of BE is ().
a2 b . 4 c . 5d . 3
Fill in the blanks (3 points for each small question, 24 points for * * *)
13. As shown in the figure, in the unequal △ABC, the straight line DE∨BC,? ADE=60？ , the number equals 60? There is another corner.
14. A piece of paper with the same width is folded in half as shown in the figure, and then what? 1= .
15. As shown in the figure, you know? 1=? 2, adding conditions can make CM∨EN. (Just write one)
16. as shown in the figure, AB∨CD, BC∨DE, if? B=50？ And then what? The degree of d is.
17. As shown in the figure, among the seven angles marked with horn numbers, * * has _ _ _ _ pairs of internal dislocation angles, _ _ _ _ pairs of congruent angles, and _ _ _ _ pairs of identical angles.
Lateral internal angle.
18. The cargo ship is 62? Sail in the right direction and then turn right 28 to avoid the reef? And then turn left 28? At this point, the sailing direction of the cargo ship is.
19. As shown in the figure, if? 1=82? ,? 2=98? ,? 3=77? And then what? 4= .
20. As shown in the picture, you know? 1=? 2,? =35? And then what? 3=_____.
Iii. Answering questions (***40 points)
2 1.(8 points) Known: as shown in the figure,? BAP+？ APD= 180？ ,? 1=? 2. verification:? E=？ F.
22.(8 points) As shown in the figure, which angles can be measured to judge whether AB is parallel to CD? Please write three plans and explain the reasons.
23.(8 points) As shown in the figure, AE∨BD, C is the point on BD, AB=BC,? ACD= 1 10？ , beg? EAB degrees.
24.(8 points) As shown in the figure, you know? ABC=90？ ,? 1=? 2,? DCA=？ Taxi, try to explain: CD split equally? Ace.
25.(8 points) As shown in the figure, in quadrilateral ABCD, AD∨BC, BC >；; AD, translate AB and CD into EF and EG respectively. If AD=4 cm and BC=8 cm, find the length of FG.
20 17 answers to the first chapter of the second volume of seventh grade mathematics 1. C analysis: ∫DE∨BC, DEB=? EBC？ ADE=？ ABC，？ AED=？ ACB。
And ∵ share? ABC，ABE=？ Is that EBC? ABE=？ Debenture corporate bonds
? There are five equilateral angles in the picture * * *, so choose C.
2.d analysis: As shown in the figure, 5=? 1=55? , because l 1∨L2, so? 4=? 2=62? , from the triangle interior angle sum theorem? 3= 180? -? 4-? 5= 180? -62? -55? =63? .
3.c analysis: from the point of view of the meaning of the question, what is it? 1+? 2=60? , so? 2=60? -? 1=60? -35? =25? .
4.c analysis: as shown in the figure, point c is CM∨AB,? .
∫AB∨EF，？ CM∨EF。
∵ ,? , ,
? .
5.b analysis: because? EAB=45？ , so? Bad = 180? -? EAB= 180？ -45? = 135? . because
AB∨CD, so? ADC=？ Bad = 135? , so? FDC= 180？ -? ADC=45？ So choose B.
6.b analysis: ∫QR∨OB, AQR=? AOB=28？ ,? PQR+？ QPB= 180？ .
From the essence of reflection? AQR=？ OQP=28？ ，PQR= 180？ -28? -28? = 124? ,
QPB= 180？ -? PQR= 180？ - 124? =56? .
7.A
8.c analysis:? BGH= 180？ -? Age = 180? -60? = 120? , by AB∨CD, get? EHD=？ BGH= 120？ .
9.c analysis: when AB is perpendicular to the straight line a, the length of AB is the distance between a and b, that is, the distance between a and b is 2 cm; When AB is not perpendicular to the straight line A, the distance between A and B is less than 2 cm, so the distance between A and B is less than or equal to 2 cm, that is, not more than 2 cm, so C.
10. An analysis: demand? 2 degrees, according to the nature of the vertex angle, can be obtained? 2=? 3. That's why you found out? 3 degrees can solve the problem. Because a∨b, according to? Two straight lines are parallel and at the same angle? , available? 3=? 1=60? , so? 2=? 3=60? .
1 1.b Analysis: Can we know from the essence of folding? BFE= =65？ Because AD ∨ BC, so? AEF= 180？ -? BFE= 1 15？ .
12.b analysis: from the essence of translation, we know that BC=EF, that is, BE=CF,
13.？ B
14.65? Analysis: 2 According to the meaning of the question? 1= 130? , the solution? 1=65? So fill in 65? .
15. The answer to this question is not unique. You can add DM∨FN.
16. 130? Analysis: Because AB∨CD, so? B=？ C=50？ Because of BC∨DE, so? C+？ D= 180？ , so? D= 180？ -50? = 130? .
17.4; 2; 4 analysis: * * * has 4 pairs of internal angles, which are? 1 and? 4,? 2 and? 5,? 6 and? 1,? 5 and? 7; 2 pairs of isosceles angles: What are they? 7 and? 1,? 5 and? 6; 4 pairs of ipsilateral internal angles: What are they? 1 and? 5、? 3 and? 4、? 3 and? 2、? 4 and? 2.
18. No.62 northwest? Analysis: Judging from the same angle and parallel line, the cargo ship has not changed its sailing direction.
19.77?
20.35? Analysis: Because? 1=? 2, so AB∨CE, so? 3=? B.
Again? B=35？ , so? 3=35? .
2 1. Proof: BAP+? APD= 180？ ,
? AB∨CD。 BAP=？ armored personnel carrier
Again? 1=? 2、BAP 1=？ Is that APC2? EAP=？ APF，
? AE∨FP。 E=？ F.
22. Solution:? EAB=？ c？ AB∨CD (same angle, two straight lines are parallel);
? Bad =? d？ AB∨CD (internal dislocation angles are equal and two straight lines are parallel);
? BAC+？ C = 180 ab∑CD (complementary to the inner angle on the same side, with two straight lines parallel).
23. Solution: AB = BC and BAC=? ACB= 180？ - 1 10? =70? .
B= 180？ -702=40? .
∫AE∨BC，EAB=？ B=40？ .
24. Solution: ∵? DCA=？ Cab (known),
? AB∑CD (internal dislocation angles are equal and two straight lines are parallel),
ABC+？ BCD= 180？ The two straight lines are parallel and complementary.
∵ ? ABC=90？ (known), BCD=90? .
∵ ? 1+? 2+? ACD+？ DCE= 180？ (definition of right angle),
2+? DCE=90？ , 2+? DCE=？ 1+? ACD。
∵ ? 1=? 2 (known), DCE=? ACD。
? CD split equally? Definition of angular bisector
25. Solution: Because AD∨BC, AB is translated into EF, and CD is translated into EG.
So AE=BF, DE=CG, so AE+DE=BF+CG, which means AD=BF+CG.
Because AD=4 cm, BF+CG=4 cm.