a) 6(x+y)=10y y-x=0,5 6x+6y=10y y=0,5+x 6x+0,5+x=(0,5+x)10 y=0,5+x 7x+0,5=5+10x y=0,5+x -3x=4,5 y=0,5+x x=-1,5 y=0,5+x x=-1,5 y=-1 b) 10(y+2)+3(x-5)=x-5 25(y+2)+3(x-5)=-10 10y+20+3x-15=x-5 25y+50+3x-15=-10 10y+2x=-10 25y+3x=25 2x=-10-10y 25y+3x=25 x=-5-5y 25y+3x=25 x=-5-5y 25y+3(-5-5y)=25 x=-5-5y 25y-15-15y=25 x=-5-5y 10y=40 x=-5-5y y=4 x=-5-20 y=4 x=-15 y=4 c) 2(2x-y)+3(x+3y)=42 5(x+3y)-8(2x-y)=-32 4x-2y+3x+9y=42 5x+15y-16x+8y=-32 7x+7y=42 |:7 23y-11x=-32 x+y=6 23y-11x=-32 x=6-y 23y-11x=-32 x=6-y 23y-11(6-y)=-32 x=6-y 23y-66+11y=-32 x=6-y 34y=34 x=6-y y=1 x=5 y=1 Oczywiście wszystko bierzesz w klamerki po bokach. ;p
a) 6(x + y) = 10y y - x = 0,5 6(x + y) = 10y y = 0,5 + x 6(x + 0,5 + x) = 10(0,5 + x) y = 0,5 + x 6x + 3 + x = 5 + 10x y = 0,5 + x -3x = 2 /(-3) y = 0,5 + x x = -⅔ y = 0,5 - ⅔ x = -⅔ y = ½ - ⅔ x = -⅔ y = -⅙ b) 2(2x-y)+3(x+3y)=42 5(x+3y)-8(2x-y)=-32 4x-2y+3x+6y=42 5x+15y-16x+8y=-32 7x=42-4y /7 5x+15y-16x+8y=-32 x=7-⁴/₇y 5(7-⁴/₇y)+15y-16(7-⁴/₇y)+8y=-32 x=7-⁴/₇y 35-²⁰/₇y+15y-112+⁶⁴/₇y+8y=-32 x=7-⁴/₇y 35y=-32 /35 x=7-⁴/₇y y=-³²/₃₅ x=7-⁴/₇(-³²/₃₅) y=-³²/₃₅ x=7+¹²⁸/₂₄₅ y=-³²/₃₅
