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Which equation can be used to solve for the unknown number? seven less than a number is thirteen. n-7=13 7-n=13 n+7=13 n+13=7

An airplane consumes fuel at a constant rate while flying through clear skies, and it consumes fuel at a rate of 64 gallons per minute while flying through rain clouds. let c represent the number of minutes the plane can fly through clear skies and r represent the number of minutes the plane can fly through rain clouds without consuming all of its fuel. 56c+64r < 900056c+64r< 9000 according to the inequality, at what rate does the airplane consume fuel while flying through clear skies, and how much fuel does it have before takeoff? the airplane consumes fuel at a rate of gallons per minute while flying through clear skies, and it has gallons of fuel before takeoff. does the airplane have enough fuel to fly for 60 minutes through clear skies and 90 minutes through rain clouds?

How many real-number solutions does the equation have? -4x^2 + 10x + 6 = 0 a. no solutions b. two solutions c. infinitely many solutions d. one solution