,7), B(5,-5) and C(10,7). The area of △ABC is A.50 B.60 C.80 D.120 E.140 30.△ABC is an isosceles right triangle with ∠B=90°. If A(3,-2),B(2,-1), then AC=… A. 2 B.1 C.2 D.3 E.4 What is the perimeter of

statement is (are) true? 1.If m>0 , then the segment makes an actual angle with the positive direction of X-axis. 2. If m<0 , the line segment makes an obtuse angle with the positive direction of

2-1-1-1is A.2 B.-2 C.-12 D.14 E.12 7.532532 =……. A.1 B.0 C.25 D.125 E.625 8.-1-1 +-10 =………. A. 2 B.1 C.0 D. -1 E.-2 Which of the following is (are) false? 1.a+b2 =a2 +b2 2.a+b =a +b 3.(ab)2 =a2b2 A.1 only