SWBAT make clear connections between the perspective art project and dilations on the coordinate plane from a center point of dilation.

This lesson will really help your students connect the dots between the perspective art project and the math of performing dilations on the coordinate plane using similar triangles.

10 minutes

I opened the lesson by re-examining the learning goals listed at the start of the activity. I let them know that today would focus on the mechanics of dilations when centered somewhere other than on the origin. I asked students to vote quickly on two options: when dilations are centered at the point (0,3) you can follow the same property of multiplying the scale factors by each x and y coordinate to properly dilate the triangle and then no you cannot follow the same property. I made it known that this dilation is straight from a high school lesson on dilations but graphing the line y = x + 3 is from 8th grade math. We are going to explore the relationship each triangle has to the line when dilated from the point (0,3). Then I read all the student conjectures about how the project relates to dilations on the coordinate plane recorded the day before on a poster. I opened the floor for new conjectures (hypothesis) about how the mechanics of the project are related to the mechanics of performing a dilation on the coordinate plane. Then we all agreed on the goals for the day and moved into completing graph two today.