Question

va rooog plâng!!!!!!!! ​

Answer 1

a)a/4=b/5

a+b=18

a/4=b/5=k=>a=4k

b=5k

=>4k+5k=18

=>9k=18

=>k=2

=>a=8

=>b=10

b)a/3=b/5

3a+2b=38

a/3=b/5=k=>a=3k

b=5k

=>3•3k+2•5k=38

=>9k+10k=38

=>19k=38

=>k=2=>a=6

b=10

c)a/2=b/3=c/4

5a+3b-c=45

a/2=b/3=c/4=k=>a=2k

b=3k

c=4k

=>5•2k+3•3k-4k=45

=>10k+9k-4k=45

=>19k-4k=45

=>15k=45

=>k=3=>a=6,b=9,c=12

d)5a=8b=k

a+b=26

=>a=k/5

=>b=k/8

=>k/5+k/8=26(aducem la acelasi numitor,numitorul comun fiind 40)

=>8k/40+5k/40=26

=>13k/40=26

=>13k=26•40

=>13k=1040

=>k=80

=>a=80/5=16

=>b=80/8=10