Robert is preparing a poster-board presentation. He wants to make a decorative pattern with 10 squares to fill part of the poster. The area of the poster board is 720 square inches. To find how much space Robert will have left for his presentation if he uses squares with 7-inch sides, evaluate 720 − 10s2

720



10
𝑠
2
when s = 7
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=

1 answer

To determine how much space Robert will have left for his presentation after using the squares, we start by calculating the area of each square with a side length of \( s = 7 \) inches.

The area of one square (\( s^2 \)) is calculated as follows:

\[ s^2 = 7^2 = 49 \text{ square inches} \]

Since Robert is using 10 squares, the total area used by the squares is:

\[ 10s^2 = 10 \times 49 = 490 \text{ square inches} \]

Now, to find out how much space Robert will have left on the poster board, we subtract the area used by the squares from the total area of the poster board:

\[ 720 - 10s^2 = 720 - 490 \]

Calculating this gives:

\[ 720 - 490 = 230 \text{ square inches} \]

Therefore, the amount of space Robert will have left for his presentation is 230 square inches.