S (ABCD) = S (ABC) + S (ADC)
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Reminder :
Area of the triangle = ½ × base × height
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Thus :
[tex]S (ABCD) = ( \frac{1}{2} \times 10 \times 3) + ( \frac{1}{2} \times 10 \times 5) \\ [/tex]
[tex]S (ABCD) = 15 + 25[/tex]
[tex]S (ABCD) = 40 \: \: {cm}^{2} [/tex]
There you go...
Have a great day ❤
