A rectangle has dimensions in feet as shown in the figure it is 2x +5
And one side is 8. I need to write an expression for the area of the rectangle.
B. Find the area of the rectangle, in sq.ft. if x=3
C. Find the value of x if the area of the rectangle is 160 square feet.
The area is length * width:
(2x+5)(8) = 16x+40
Use that in B, and then solve for x if 16x+40 = 160
(2x+5)(8)=16x+40 or 4x+4x+4x+4x+5(8)
x=3 then solve for x if 16x+40=160
To write an expression for the area of a rectangle, we need to multiply the length by the width. In this case, the length is given as 2x + 5, and the width is 8.
So, the expression for the area can be written as:
Area = (2x + 5) * 8
Now let's move on to the questions:
B. To find the area of the rectangle when x = 3, we substitute the value of x into the expression:
Area = (2(3) + 5) * 8
Area = (6 + 5) * 8
Area = 11 * 8
Area = 88 square feet
C. To find the value of x when the area of the rectangle is 160 square feet, we set up an equation by equating the area expression to 160:
(2x + 5) * 8 = 160
Now we can solve for x:
16x + 40 = 160
16x = 120
x = 120/16
x ≈ 7.5
So, the value of x, when the area of the rectangle is 160 square feet, is approximately 7.5.