1.8 plus or minus 8 4 2. Plus or minus 9 minus 1/2 3.0, 1, 2 radical number 2, negative radical number 2, radical number 3 4. Plus or minus 2/5. Select less than 1-5cbbbb to solve the problem1. Add and subtract 5, not add and subtract 3, add and subtract 3/2. No computer.
two
1 .32.13.-54.1.6965.-1and negative root number 2 1-5 BBCAD to solve the problem1. (1) minus one-fifth (2) No computer 2.
three
1. 10, eight times x, six times a, eleven times a, squared 2. A, twelve times 10, six times a, three times three. -4A, four times b, four times y, four times 4. -6A, three times +2AB, squared two-thirds x, squared 2x- three-fifths. Select 65438. 6 times of 38+0. m，2。 Five times that of B and five times that of 3. X, 6n-65438+0 times of 4.3x and 5 times of 5. -(2A-B), 6.4A, etc. Square B- three, 7. 1.
four
The quadratic of 1 A+ square of 2ax+4xy+x- square of y 2. The square of (400- 1)65438+0502013. ab4.10a (b-3) is the sixteenth square (the square of 4AB+the square of a +A+4b). Select 1-4babb and calculate it. Square of 4 of m (a+2b)
five
1.8 2.33 times the root number 3. Right angle 24 4.2 point 4 selection1-4 DCD application 1.250 (nautical mile) 2. The root number is 20.8 (meters).
3.30 degrees
six
1.30 2.2 times the number of roots 5 3. 100 4. I don't understand 5.336 1-3 1. 16 (in the sea) 2. Third. Don't understand 4. When point D is perpendicular to point A, the cost of the canal is the lowest. 480 yuan
5. (1) ∵ ∠ cab = ∠ CAD = ∠ ACD = 30 ∴ ∠ bad = ∠ cab+∠ CAD = 60 and ∵ab = ad∞. 0? 5 - OB？ 0? 5= root number 27÷oc = ao = root number 27∴AC=AO+OC=2 times root number 27.
seven
1.33 2. Symmetrical selection 1. C2.D is drawing (omitted)
eight
1.D 90 AC ACD 2 C 60 28 solution 1. (1)BC and AC CD and CE BD and AE (2) are the reasons for the omission (actually, I don't understand) (3) 60 (4) 8 2. The rotation center is point B, and the rotation angle is 60 3. 4.30
nine
1.5 60 2.3 90 3.0 40 4.2 and j 1. The answers are all wrong. 2.b triaxial symmetry (1, 4,5) rotational symmetry (123456) central symmetry (23456) four (omitted).
ten
1.75 105 2.8 9 3.80 4.9 5.24cm？ 0? 5 Select 1—5 ADAB to solve the problem 1. BC∨ef Reason ∫ad∨ad∨ef∴BC∨ef 2. ∫do = ao∴∠oad = \
From eleven to fifteen tomorrow.
Eleven 1 .6cm2.203.1204.11cm selection1. —3 BBB。
Question 1. Add AE and DF∵EF=AD∴BE+CF= half BC ∵BE=CF∴BE=CF= quarter BC = half AD ∵AB=AD∴BE= half AB ∴.
2.∫CD = BC∴∠DBC =∠CDB and ∫ab∨CD∴∠Abd =∠CDB∴∠DBC =∠Abd =
Twelve 1. x？ 0? 5-XY-6Y？ 0? 5 2. I don't understand 3.3 4.5 1-4caddd factorization1. 3B？ 0? 5(A？ 0? 5-2 BC) (2)X(X-4)(X+4) 2. Calculate (1)X? 0? 5-9Y？ 0? 5(2)4 meters? 0? 5-4MN+N？ 0? 5 (3)-5 times M (4) did not understand.
Thirteen 1. -8 2.90 3. 1cm？ 0? 5 4.2(A-B)(A+B) Choose 1-4cadb to solve problems1. ∫db sharing ∠ ABC ∴∠ Abd = ∠ DBC and ∫ad∨BC.
Fourteen 1. -3a？ 0? 5c N 3 times 2. -1, 0,13.1204.121< x < 9 Select 1-4cacc to solve the problem. Let the original side of the playground be x meters (x+. 0? 5-X？ 0? 5 = 1700 X = 8 ^ 2。 Firstly, rotate △ABC counterclockwise by 90 degrees with point A as the rotation center, then translate it by 6 units in the AC direction, and finally make an axisymmetric figure with line segment MN as the symmetry axis.
XV 1。 (x+3y) ((x-3y)-(x+3y)) 2。 < 3. I don't understand 4.20. Select 1-3 BCB to solve the problem 1. In Rt△ABD, BD= AB under the radical sign? 0? 5-AD？ 0? In Rt△ACD, 5=7, CD= radical sign, AC? 0? 5-AD？ 0? 5= 18 BC=BD+CD=25 2。 I don't understand.