1. If ∠ A = 23 34', ∠ B = 7145', ∠ A+∠A+∠B = _ _ _ _'.

2._ _ _ _ _ _ is the shortest line segment connected by points outside the line and points on the line.

3. The proposition of "equal vertex angles" is: _ _ _ _ _ _ _ _ _ _ _,

The conclusion is _ _ _ _ _ _ _ _ _ _.

4. When x _ _ _ _ _ _ _ _ _ the algebraic expression 1-3x is nonnegative.

5. Expressed in scientific notation: 0.000602 = _ _ _ _ _ _.

6. When _ _ _ _ _ _ _, (2a+ 1)0= 1.

7. Calculation: (A+2) (A-2) (A2-4) = _ _ _ _ _ _ _.

2. Multiple choice problem

1. Among the following propositions, the correct one is ().

(a) Of all the straight lines connecting two points, the straight line is the shortest.

(b) Two straight lines are cut by a third straight line and equal to the complementary angle.

(c) Two disjoint straight lines are called parallel lines.

(d) If both straight lines are perpendicular to the third straight line, the two straight lines are parallel to each other.

2. As shown in figure AB ‖ DE, ∠ B = 120, ∠ D = 25, then ∠C= ().

50 (B) 80 (C) 85 (D) 95

3. When two parallel lines are cut by a third straight line, a set of bisectors at the inner corner of the same side are mutually ().

(a) vertical (b) parallel (c) coincident (d) intersecting, but not vertical.

4. If AB ‖ CD and CD ‖ ef are known, AB‖EF. The basis of this reasoning is ().

(a) Parallel axiom (b) Equivalent substitution (c) Internal dislocation angles are equal and two straight lines are parallel.

(d) Two lines parallel to the same line are parallel.

5. If ∠A and ∠B are parallel and ∠A is 30 smaller than ∠B, then ∠B is ().

(a) 30 (b) 70 (c) 30 or 70 (d) 100.

6. In the following equation, () is wrong.

(A)(A-B)2 =(B-A)2(B)(A+2b)2 = a2+4b 2

(-A-b)2 =(A+b)2(D)(A+b)2-(A-b)2 = 4ab

7. In the following operations, the correct one is ()

(A)(3a6b)2 = 6a 12 B2(B)(8a2b-6ab 2)÷2ab = 4a-3b

(C) (D)(X-2Y)(2y-x)=x2-4xy+4y2

8.if- 1 < x & lt； 0, the value of the algebraic expression x( 1+x)( 1-x).

(a) It must be positive; (b) It must be negative; (c) It must be non-negative; (d) The pros and cons are uncertain.

Three. solve problems

1. Calculation: (3m-2n)(2n+3m)

2. Calculation: (a-3)(a2+3a+9)

3. It is known that | 2x+y-1|+(5x-4y-8) 2 = 0. Find the value of xy.

4. Calculation: (3x2-2x+1) (3x2+2x-1)

5. Calculation: (-2xay) 2 (xa-2ya) 4 ÷ [(-xy2) 2] a

6. Calculation: (m-3n)2-(3n+m)2

7. If x+y = 2, xy = k+4 and (x-y) 2 = 12, find the value of k. 。

Draw the vertical line of AB through point C, and then draw the parallel line of BC through the middle point of AC.

5. Simplify first and then evaluate: (a+2b)2(a-2b)2-(2a-b)2(2a+b)2,

Where A2 = 2 and B2 = 1.