мог бы побольше очков дать
(1;-3), (2;4), (1;2), (-1;4), (3;1)
Объяснение:
413.
{2х-3у=11
{5х+у=2 |×3
{15х+3у=6
*+*
{17х=17
{у=2-5х
{х=1
{у=2-5×1=-3
(1;-3)
416.
{5х+у=14 |×2
{3х-2у=-2
{10х+2у=28
{13х=26
{у=14-5х
{х=2
{у=14-5×2=4
(2;4)
419.
{х+3у=7
{х+2у=5 |×(-1)
{-х-2у=-5
{у=2
{х=5-2у=5-2×2=1
(1;2)
422.
{2х+3у=10
{х-2у=-9 |×(-2)
{-2х+4у=18
{7у=28
{х=-9+2у
{у=4
{х=-9+2×4=-1
(-1;4)
425.
{х-у=3 |×(-3)
{3х+4у=2
{-3х+3у=-9
{7у=-7
{х=3+у
{у=-1
{х=3-1=2
(2;-1)
428.
{х-4у=-1 |×(-3)
{3х-у=8
{-3ч+12у=3
{11у=11
{х=4у-1
{у=1
{х=4×1-1=3
(3;1)
мог бы побольше очков дать
(1;-3), (2;4), (1;2), (-1;4), (3;1)
Объяснение:
413.
{2х-3у=11
{5х+у=2 |×3
{2х-3у=11
{15х+3у=6
*+*
{17х=17
{у=2-5х
{х=1
{у=2-5×1=-3
(1;-3)
416.
{5х+у=14 |×2
{3х-2у=-2
{10х+2у=28
{3х-2у=-2
*+*
{13х=26
{у=14-5х
{х=2
{у=14-5×2=4
(2;4)
419.
{х+3у=7
{х+2у=5 |×(-1)
{х+3у=7
{-х-2у=-5
*+*
{у=2
{х=5-2у=5-2×2=1
(1;2)
422.
{2х+3у=10
{х-2у=-9 |×(-2)
{2х+3у=10
{-2х+4у=18
*+*
{7у=28
{х=-9+2у
{у=4
{х=-9+2×4=-1
(-1;4)
425.
{х-у=3 |×(-3)
{3х+4у=2
{-3х+3у=-9
{3х+4у=2
*+*
{7у=-7
{х=3+у
{у=-1
{х=3-1=2
(2;-1)
428.
{х-4у=-1 |×(-3)
{3х-у=8
{-3ч+12у=3
{3х-у=8
*+*
{11у=11
{х=4у-1
{у=1
{х=4×1-1=3
(3;1)