Look at rectangle ABCD below.
Side AB is 10 cm long and side BC is 2.5 cm long.
What is the area of the rectangle?
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Look at rectangle ABCD below.
Side AB is 10 cm long and side BC is 2.5 cm long.
What is the area of the rectangle?
Let's begin by multiplying side AB by side BC
If we insert the known data into the above equation we should obtain the following:
Thus the area of rectangle ABCD equals 25.
25 cm²
Look at the rectangle below.
Side AB is 2 cm long and side BC has a length of 7 cm.
What is the perimeter of the rectangle?
Area measures space inside the rectangle! When you multiply length × width, you're finding how many unit squares fit inside. Adding gives you part of the perimeter, which just measures the border.
The cm² means 'square centimeters' - it shows you're measuring area, not length. Always include squared units for area problems, or your answer is incomplete!
Yes! Multiplication works both ways, so 2.5 × 10 = 10 × 2.5 = 25. The order doesn't matter - you'll get the same area either way.
Think of 2.5 as 'two and a half'. So 10 × 2.5 = 10 × 2 + 10 × 0.5 = 20 + 5 = 25. Or just multiply normally and count decimal places!
You probably added instead of multiplied! Check: 10 + 2.5 = 12.5, but that's not area. Remember: area always uses multiplication, not addition.
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