Question

решите уравнение
(y-2)(y+3)-(y-2)^2=5

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Answer 1

$\boxed{(a-b)^2=a^2-2ab+b^2}\\\\\\(y-2)(y+3)-(y-2)^2=5\\\\y^2+3y-2y-2\cdot3-(y^2-2y\cdot2+2^2)=5\\\\y^2+3y-2y-6-(y^2-4y+4)=5\\\\y^2+3y-2y-6-y^2+4y-4=5\\\\(3-2+4)\cdot y+(-6-4)=5\\\\5y-10=5\\\\5y=5+10\\\\5y=15\\\\y=\dfrac{15}{5}\\\\y=3$