Question

Folosind proportii derivate,aflati x din : a) x+1 supra x = 6 supra 7
b) x supra x+2 =7 supra 9
c) x supra 8 = x+1 supra 9
Va rog mult mine am scoala si trebuie sa le fac ! multumesc !!

Answer 1

a)(x+1)/x=6/7
7(x+1)=6x
7x+7=6x
7x-6x=-7
x=-7

b)x/(x+2)=7/9
9x=7(x+2)
9x=7x+14
9x-7x=14
2x=14
x=14/2
x=7

c)x/8=(x+1)/9
9x=8(x+1)
9x=8x+8
9x-8x=8
x=8