A) the perimeter of a triangle is the bottom plus the left slanty side plus the right slanty side, but you need the bottom in ft so that would be 6 ft. the perimeter is 13 ft
b) 1 yard
If I did this right it should be 8.
Part(A):
To solve the system of Linear equations using Substitution:

Consider the first equation, x+y=7 implies x=7-y













PArt(B): Use a graph to verify your answer to the system:
Using Desmos graphing calculator, graph the two equations.
Step-by-step explanation:
Suppose that the weight (in pounds) of an airplane is a linear function of the amount of fuel (in gallons) in its tank. When carrying 15 gallons of fuel, the airplane weighs 2187 pounds. When carrying 35 gallons of fuel, it weighs 2303 pounds. How much does the airplane weigh if it is carrying 50 gallons of fuel?
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You have two points relating fuel and weight.
(15,2187) and (35,2303)
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slope = (2303-2187)/(35-15) = 5.8
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intercept = ?
2187 = 5.8*15 + b
b = 2100
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Equation:
f(x) = 5.8x + 2100
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f(50) = 2390 lbs.
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The area would be length times width so the answer is 648 squared inches!