Przed dwoma laty matka była 4 razy starsza od Syna za dziesięc lat będą mieli razem 74 lata Ile lat ma obecnie każdy z nich . ? prosze o rozpisanie tego zadania, i rozwiązanie :).
isiaczek777
A- syn b- mama 4(a-2)=b-2 4a-8=b-2I+8 4a=b+6
b+a+20=74|-20 b+a=54 b=4y-6 4a-6+a+20=74 5a=60I:5
a=12
b=4a-6 b=4*12-6 b=42
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ainaaa94
| Teraz | Dwa lata temu | Za dziesięć lat `````````````````````````````````````````````````````````` Mama| x | x-2 | x+10 `````````````````````````````````````````````````````````` Syn | y | y-2x | y+10 ``````````````````````````````````````````````````````````
b- mama
4(a-2)=b-2
4a-8=b-2I+8
4a=b+6
b+a+20=74|-20
b+a=54
b=4y-6
4a-6+a+20=74
5a=60I:5
a=12
b=4a-6
b=4*12-6
b=42
``````````````````````````````````````````````````````````
Syn | y | y-2x | y+10
``````````````````````````````````````````````````````````
To miała być tabelka ale nie wyszła coś
Obliczyć to trzeba za pomocą układy równań
x+10+y+10=74
x-2=4(y-2)
x+y+20=74
x-2=4y-8
x+y=74-20
x-4y=-8+2
x+y=54
x-4y=-6/*(-1)
x+y=54
-x+4y=6
+~~~~~~~~
5y=60/:5
y=12
y=12
x+12=54
y=12
x=54-12
y=12
x=42
Odp.: Mama ma 42 lata, a jej syn 12