Answer:
D
Step-by-step explanation:
it -4<x<8 your answer is d
Robert Morris, generally considered the financier of the Revolution, donated ships from his fleet of tobacco-trading vessels and turned to privateering. Raiding British convoys, he became the richest man in America. He personally signed 6,000 notes to pay off Washington's troops when the war ended.
Area of rectangular board = length (inches) x width (inches) = 12" x 16" = 192 in²
Area of the border is given as 128 in²
Adding the area of the board and the border gives (192 + 128)in² = 320 in²
Set this up as the algebraic equation (x + 12)(x + 16) = 320 and solve for x:
Remember to use the FOIL method, which is multiplying the terms in the order of first, outer, inner, last.
x² + 12x + 16x + 192 = 320
x² + 28x + 192 - 320 = 0
x² + 28x - 128 = 0
solve for the two x values:
(x + 32)(x - 4) = 0, and knowing we only need the positive x value
x = 4 or 4 inches is the width of the border
