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The sum of the areas of two rectangles is 212 m². The second rectangle is 12 m² smaller than three times the first rectangle. What are the areas of the rectangles?​

User Matt Price
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Given:

Given that the sum of the areas of two rectangles is 212 m². The second rectangle is 12 m² smaller than three times the first rectangle.

We need to determine the areas of the two rectangles.

Equations of the two rectangles:

Let a₁ denote the area of the first rectangle.

Let a₂ denote the area of the second rectangle.

The equations of the two rectangles is given by


a_1+a_2=212 and
a_2=3a_1-12

Areas of the two rectangles:

The areas of the two rectangles can be determined using substitution method.

Thus, substituting
a_2=3a_1-12 in the equation
a_1+a_2=212, we get;


a_1+3a_1-12=212


4a_1-12=212


4a_1=224


a_1=56

Thus, the area of the first rectangle is 56 m²

Substituting
a_1=56 in the equation
a_2=3a_1-12, we get;


a_2=3(56)-12


a_2=168-12


a_2=156

Thus, the area of the second rectangle is 156 m²

Hence, the area of the two rectangles are 56 m² and 156 m²

User Nakeia
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