You would have to divide $16.76 by 4 to find out how much 1 gallon costs and after that multiply the amount a gallon costs by 7 to get your answer
8.9. round the first 8 after decimal to 9 because the 8 after is 5 or above.
(x-3)(x+7) —> multiply them together I do it by FOIL which stands for Firsts Inners Outers Lasts
x’(squared)+7x-3x-21 —> simplify
x(squared)+4x-21
Answer:
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Step-by-step explanation:
This system we can solve by substitution method :
y=13x-1
y=9x+4
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y=13x-1
13x-1=9x+4 (instead y in second equation we use 13x-1 and first rewrite)
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y=13x-1
13x-9x=4+1 (subtract 9x and add 1 for each side)
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y=13x-1
4x=5 (divide by 4)
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y=13x-1
(instead x in first eq we write 5/4)
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