Question

Ex 9 va rog! Am nevoie pentru maine la algebra

Answer 1

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Answer 2

a) x/4 = 3/5  
    x = (4*3)/5 = 12/5

b) 10/x = 1/4
x = (10*4)/1 = 40

c) 4/9 = x/2
    x = (4*2)/9 = 8/9

d) 3/8 = 9/x
    x = (9*8)/3 = 3*8 = 24

e) x/(1/3) = (7/10) / (3/10) 
    x/(1/4) = (7/10) * (10/1) = 7/1 = 7
    x = 7*(1/4) = 7/4

f) 0,4/x = 0,05/0,3
    x = (0,4 * 0,3) / 0,05 = 0,12/0,05 = 12/5

g) x/0,5 = 0,7/0,35
    x = (0,5 * 0,7)/0,35 = 0,35/0, 35 = 1

h) (1/2 + 1/5) / x = 7/10
    x = [(1/2 + 1/5) * 10] / 7 = [(5/10 + 2/10) * 10]/7 = [{7/10) * 10]/7 = 7/7 = 1

i) x/16 = (0,75 + 1/4)/8
    x = [16 * (3/4 + 1/4)]/8 = (16 * 4/4)/8 = 16/8 = 2

j) [1/4 + (1/4):4]/15 = x/4
    x = 4*[1/4 + (1/4)*(1.4)]/15 = 4*(1/4+1/16)/15 = 4*(4/16 + 1/16)/15 = 4*(5/16)/15 = (5/4)/15 = (5/4)*(1/15) = 1/12

cele cu perioade nu le stapanesc bine, dar celelalte sunt sigur corecte