Răspuns :
Răspuns:
a+b=980
a+64=3(b+32)
a+64=3b+96
a=3b+96-64
a=3b+32
3b+32+b=980
4b=980-32
b=948:4=>b=237
a=980-237=>a=743
_______________
a+b = 25=>a=25-b
2a+3b=65
2·(25-b)+3b=65
50-2b+3b =65
b+50=65=>b=65-50=15=>b=5
a=25-15=>a=10
Răspuns:
Explicație pas cu pas:
A)
[tex]a+b=980\\a+64=3(b+32) => a+64=3b+96 => a=3b+96-64 => a=3b+32\\3b+32+b=980 \\\\4b + 32 = 980\\\\4b = 980 - 32\\b=948:4 \\\\b=237\\a = 980 - 237\\ \\a=743[/tex]
B)
[tex]a+b = 25 => a = 25 - b\\a+15=2*(b+2) \\a+15 = 2b+4\\a = 2b +4-15\\a = 2b-11\\25-b = 2b -11 \\\\25 +11 = 2b+b\\\\36 = 3b\\\\b = 12\\\\a = 12*2-11\\a= 13[/tex]