Question

Ashwin helps paint a square mural in his classroom. Then he helps paint a mural in the hallway whose length is 7 feet longer and whose width is 3 feet shorter. Let x represent the side length of the mural in ashwins classroom. Write an expression that represents the two binomials you would multiply to find the area of the hallway mural. Use that expression to find the area of the hallway mural. Use that expression to find the area of the hallway mural if each side of the classroom mural is 8 foot long.

Answer 1

(x+7)(x-3); 75 square feet

Explanation:

Answer 2

Ashwin paints 2 murals:

1. A square mural in his classroom
2. A mural in the hallway with length 7 feet longer and width 3 feet shorter

Also, x indicates the side length of the mural in the classroom. Since the classroom mural is square in shape, the length and breadth of the mural would be x.

Part A: Expression to represents the two binomials to be multiplied to find the area of the hallway mural

Area of the hallway mural = Length of the hallway mural × Breadth of the hallway mural

So Length of the hallway mural = Length of the classroom mural + 7

⇒ Length of the hallway mural = x + 7

Breadth of the hallway mural = Breadth of the classroom mural - 3

⇒ Breadth of the hallway mural = x - 3

Hence, x + 7 and x - 3 need to be multiplied to determine the area of the mural

Part B: Area of the hallway mural

Area of the hallway mural = Length of the hallway mural × Breadth of the hallway mural

⇒ Area of the hallway mural = (x + 7) × (x-3)

⇒ Area of the hallway mural = x² + 7x - 3x - 21

⇒ Area of the hallway mural = x² + 4x - 21

Part C: Area of the hallway mural if each side of the classroom mural is 8 foot long

Putting the value x = 8 in the answer of Part B

⇒ Area of the hallway mural = 8² + 4×8 - 21

⇒ Area of the hallway mural = 64 + 4×8 - 21

⇒ Area of the hallway mural = 64 + 32 - 21

⇒ Area of the hallway mural = 75 square feet