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Solve each equation by either substitution or addition method.

x2 + 4y2 = 20
x + 2y = 6

1 Answer

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Answer: (2,2), (4,2)

First, I subtracted 2y from both sides of the second equation. Then, I substituted -2y+6 in for x in the first equation (-2y+6)²+4y²=20. Then, I expanded 4y²-24y+16+4y²=20. Next, I combined like terms, and moved everything to one side 8y²-24y+16=0. Then, I factored out an 8, and then finished factoring 8(y-2)(y-1). This gives me my y-values, y=1,2. Next, I inserted each y-value into the second equation and got x=-2(1)+6 ---> x=4 (The first solution is (4,1). ) and x=-2(2)+6----->x=2 (The second solution is (2,2).

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