Answer:
42 square units
Step-by-step explanation:
The area of the rectangle is the product of its length and width:
area = 6(x -8)
The area of the triangle is half the product of its base and height:
area = (1/2)(x-3)·7
These two areas are equal, so we have ...
6(x -8) = (1/2)(x -3)(7)
6x -48 = 3.5x -10.5 . . . . eliminate parentheses
2.5x = 37.5 . . . . . . . . . . . add 48 -3.5x
x = 15 . . . . . . . . . . . . . . . divide by 2.5
The area of the rectangle is ...
area = 6(15 -8) = 42 . . . . square units.
