Plz do both plz plz plz

3. C or 18.

4. Perimeter: 10 Area: 6.25

5. 3 and 16

Step-by-step explanation:

3. Because the area of a triangle is 1/2 the base times the height if you double the area you can divide this total area by one side to find the length of the other side. In this problem that is 72*2 which is 144. Then dividing 144/8 you get 18, which is answer choice C.

4. Since a square has 4 sides that are all the same, you only need to know one side length to know them all. Multiplying one side length (2.5) by itself will get you the are of the square as a whole. Doing this (2.5 multiplied by 2.5 gets the area of 6.25.

For the perimeter calculation use the formula for a perimeter of a square which is one side (2.5) multiplied by 4 is 10, which is the perimeter.

5. This is because 3*16 is 48 or the area of the rectangle.

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step-by-step explanation:

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