Rectangles: 3540

The dimensions of the left rectangle are 4 cm and (x+1) cm. The right rectangle consists of two rectangles: the upper one with dimensions of 3 cm and x cm and the lower one with an area of 7 cm². We know that the area of the left rectangle is the same as the area of the right rectangle. Determine x.

Correct answer:

x =  3

Step-by-step explanation:

$$\begin{gathered} S_1=S_2 \\ {S}_1=4\cdot (x+1) \\ {S}_2=3\cdot x+7 \\ 4(x+1)=3x+7 \\ 4\cdot (x+1)=3\cdot x+7 \\ x=3 \\ x=\frac{3}{1}=3 \\ x=3 \end{gathered}$$

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