Pls help me I will give u 100 points and mark you as brainiest pls help. 1,2,3,4,5

See explaination

Step-by-step explanation:

All these questions can be solved remembering that the area of a triangle is the base*height/2

1) 9.8*3.6/2 = 17.64

2) 14*35/2  = 245

3) 8.4*6.9/2 = 28.98

4) For this one, it is important to realize that if a triangle contains 2 perpendicular lines, it is a right triangle, and therefore, those two lines must be the base and the height. So the answer is just 1.8*2.5/2 = 2.25

5)3.2*9.6/2 = 15.36