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Geometry Difficulty 1.1 Junior Find the answer Canada

A triangle has side lengths $3~\text{cm}$ , $5~\text{cm}$ , and $x~\text{cm}$ , as shown.If the perimeter of the triangle is $12~\text{cm}$ , the value of $x$ is

Pick one

Solution

The perimeter is $12 \text{ cm}$ . Thus, $3 \text{ cm} + 5 \text{ cm} + x \text{ cm}=12 \text{ cm}$ , and so $x=12-8=4$ .

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