Q:

The sides of ∆ABC are 30 units, 40 units, and 60 units long. The corresponding sides of ∆XYZ are r times as long as the sides of ∆ABC. The expression that gives the perimeter of ∆XYZ is . If the area of ∆ABC is n square units, the area of ∆XYZ is square units. NextReset

Accepted Solution

A:
Answer:Perimeter is 130r unitsArea is n*r^2 square unitsStep-by-step explanation:So, something special happens to perimeter and area if you scale a figure by some factor.  let's say you make a figure twice as big, well, the perimeter also gets twice as big.  Area though will get 4 times as big.  more generally, if you scale a figure by x, the perimeter also scales by x, while the area scales by x^2.So for this triangle, the perimeter of abc is 30 + 40 + 60, then when you scale them by r the perimeter becomes 30r + 40r + 60r or (30 + 40 +60)r.  of course 30 + 60 + 40 is 130 so the perimeter of xyz is 130rNow for area, the problem just vices us the area as n.  Scaling the sides by r makes the area n*r^2.  This is for all shapes.  If you want to check try on a random triangle, or more easily a square