Question

A triangular piece is removed from the rectangle. Find the remaining area.

Answer 1

We are given a rectangle with:

• Length = 18 cm
• Width = 10 cm

And a right-angled triangle is removed from the rectangle with:

• Base = 18 – (2 + 4) = 12 cm
• Height = 10 cm
• Hypotenuse = 13 cm   ...(Used for checking, not needed for area)

Step 1: Area of the rectangle

`"Area"_("rectangle")` = 18 × 10

`"Area"_("rectangle")` = 180 cm²

Step 2: Area of the right triangle removed

`"Area"_("triangle")` = `1/2 xx  "base" xx "height"`

`"Area"_("triangle") = 1/2 xx 12 xx 5`

`"Area"_("triangle")` = 30 cm²

Step 3: Remaining area

Remaining Area = 180 – 30

Remaining Area = 150 cm²