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解方程组:{5x+10=10y,15x=20y+10

题目详情
解方程组:{5x+10=10y,15x=20y+10
▼优质解答
答案和解析
5x+10=10y ==> x + 2 = 2y ==> x = 2y-2
15x=20y+10 ==> 3x = 4y + 2
==> 3 * (2y-2) = 4y + 2
==> 6y - 6 = 4y + 2
==> 2y = 8
==> y = 4
x = 2y - 2 = 2 * 4 - 2 = 6
x = 6
y = 4