 Hello all and welcome to the session. Today the question is a triangle whose area is 18 cm2 is transferred under enlargement about a point in space. If the area of its image is 648 cm2 find the scale factor of enlargement. Now before starting the solution of this question we should know about the formula which is area of image is equal to k square times area of pre-image and where k is the scale factor by which the given figure is enlarged. Now this formula will work as the key idea for solving out this question and now we will start with the solution. Here we have to find out the value of enlargement factor it means we have to find out the value of k. Now area as the given triangle which means area as the pre-image is equal to 18 cm2. Also it is given area of resulting figure which means area of image is equal to 648 cm2. Now according to the formula which is given in the key idea area of the image is equal to k square times area of the pre-image. Therefore area of the image which is 648 cm2 is equal to k square times area of the pre-image which is 18 cm2. This implies k square is equal to 648 over 18. Now 18 into 36 is equal to 648 so this implies k square is equal to 36. This implies k is equal to square root of 36 which is equal to 6. Thus the scale factor of enlargement is equal to 6. So this is the solution of the given question. That's all for this session. Hope you all have enjoyed this session.