Теңдеулер жүйесін қосу тәсілімен шешіңіз:{2х+5у-16=0;-2х-7у+20=0

Question

Математика: Теңдеулер жүйесін қосу тәсілімен шешіңіз:{2х+5у-16=0;-2х-7у+20=0

курлык35 · Accepted Answer

1) x-2/6 + x/2 = 5x-2/9;
х+х/2-5х=2/6-2/9
х(1+1/2-5)=6/18-4/18
х(2/2+1/2-10/2)=1/9
-7/2х=1/9
х=1/9:(-7/2)
х=1/9×(-2/7)
х=-2/63
2) 5+2x/3 = x-3/5 + x+5/2;
2х/3-х-х=5/2-3/5-5
х(2/3-1-1)=25/10-6/10-50/10
х(2/3-3/3-3/3)=(-31/10)
-4/3х=(-31/10)
х=(-31/10):(-4/3)
х=(-31/10)×(-3/4)
х=93/40
3) 3(x+1)/8 + 2(5-x)/3 = 16-13x;
3/8х+3/8+10/3-2/3х=16-13х
3/8х-2/3х+13х=16-3/8-10/3
х(3/8-2/3+13)=384/24-9/24-80/24
х(9/24-16/24+312/24)=295/24
305/24х=295/24
х=295/24:305/24
х=295/24×24/305
х=295/305
х=59/61
4) 5(7-2x)/3 - 4x-2/9 = x-19/2.
35/3-10/3х-4х-2/9-х=-19/2
-10/3х-4х-х=-19/2-35/3
х(-10/3-4-1)=-57/6-70/6
х(-10/3-15/3)=-127/6
х(-25/3)=-127/6
х=-127/6:(-25/3)
х=-127/6×(-3/25)
х=127/50

MOGZ ответил