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Lawrence Zu Xin Wong

Asked 9 years ago

SG Primary 5 Measurement

please help to solve. thanks in advance

Replies 3

Yeo Robert

Since AE + ED = BF = FC, EF is a hortizontal line cutting the rectangle into two rectangles. So the shaded region are two triangles. Area of triangle would be 1/2 DC x 1/2 AD = 1/4 AD x DC = 38 cm2 Total area of rectangle would be 4 x 38 = 152 cm2.

6 years ago

Shaoyang Brandon

Hi, Wong Zu Xin Lawrence! Let me give you two hints! Hint 1: Base of smaller shaded triangle + Base of bigger shaded triangle = EF Hint 2: The height of the smaller and bigger shaded triangles are the same because AE=ED. Hint 3: Area of the shaded triangles is the same area as triangle BEF when you join Point B and Point E. You can now solve for the area of rectangle ABCD.

6 years ago

Mike Tan

38 x 4 = 152 sq cm

6 years ago

Maya Tharangani

Asked 9 years ago

SG Primary 4 Number and Algebra

Replies 2

Shaoyang Brandon

Figure 1: 1 square Figure 2: 2x2 squares Figure 3: 3x3 squares Figure n: nxn squares Figure 1: 1 circle Figure 2: 1+2 circles Figure 3: 1+2+3 circles Figure n: 1+2+3+...+n circles. :)

6 years ago