Exercise 35 Page 26

Practice makes perfect

a The area of a rectangle is calculated by multiplying the rectangle's length, l, with its width, w.

A= l * w ⇕ A= ( 3y+4)( 6y-5) We can use the FOIL Method to product of these binomials.

(3y+4)(6y-5)

Multiply parentheses

(3y)(6y)+(3y)(- 5)+(4)(6y)+(4)(- 5)

18y^2-15y+24y-20

Add terms

18y^2+9y-20

The area of the court is 18y^2+9y-20 ft^2.

b The length of the volleyball court is represented by 3y+4, so it should be equal to 31.

3y+4= 31 ⇒ y=9We can find its width (6y-5) by substituting 9 for y.

6y-5

y= 9

6( 9)-5

▼

Evaluate

54-5

Subtract term

The width of the court is 49 feet. We will now multiply the width and length to find the area. A&=31* 49 &= 1519 The court has an area of 1519 ft^2.

Exercises p.25-27

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