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, 2013

Algebra Difficulty 1.4 Junior Find the answer Canada

If $x=4$ and $3x+2y=30$ , what is the value of $y$ ?

Pick one

Solutions — 2

Solution 1

Substituting $x=4$ into $3x+2y$ we get, $3(4)+2y=12+2y$ .

Since this expression $12+2y$ is equal to 30, then $2y$ must equal $30-12$ or 18.
If $2y=18$ , then $y$ is $18\div2$ or 9.

Solution 2

Each face of a cube is a square. The dimensions of each face of the cube are 1 cm by 1 cm. Thus, the area of each face of the cube is $1\times1=1$ cm $^2$ .
Since a cube has 6 identical faces, the surface area of the cube is $6\times1=6$ cm $^2$ .

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