The area of a triangle is 124 square units. what would it's new area be if its base was half as long and its height was three times as long?

To solve this problem you must apply the proccedure shown below:

 1. You have that the formula for calculate the area of a triangle is:

 A=bh/2

 Where A is the area of the triangle, b is the base of the triangle and h is the height of the triangle.

 bh/2=124
 bh=124x2
 bh=248

 2. The problem asks for the new area of the triangle if its base was half as long and its height was three times as long. Then, you have:

 Base=b/2
 Height=3h

 3. Therefore, when you substitute this into the formula for calculate the area of a triangle, you obtain:

 A'=bh/2

 (A' is the new area)

 A'=(b/2)(3)/2
 A'=3bh/4

 4. When you substitute bh=248 into A'=3bh/4, you obtain:

 A'=186 units²

 The answer is: 186 units²