Răspuns:
Explicație pas cu pas:
Prob. 7:
Din x:y=5 rezulta x=5y
5y-y=600
4y=600
y=600:4
y=150
x=150x5=750
7)
a-b=600
a:b=5=> a=b×5
5×b-b=600
4b=600/:4
b=150
a=450
8)
a+b=70
a:b=3,r2=> a=3×b+2
3×b+2+b=70
4×b =70-2
4×b=68/:4
b=17
a=70-17
a=53
9)
a-b=640
a:b=4,r13=>a=4×b+13
4×b+13-b=640
3×b=640-13
3×b=627/:3
b=209
a=640+209
a=849
