Question

Calculați numărul x știind că a-b=6. b) x*a-x*b+9a-9b=654. c) 7*a-7*b+x =55. d) 13+x-(5*a-5*b)=2011​

Answer 1

b) x(a-b)+9(a-b)=654

6x+54=654

6x=600

x=100

c) 7(a-b)+x=55

7×6+x=55

42+x=55

x=13

c) 13+x-[5(a-b)]=2011

13+x-(5×6)=2011

13+x-30=2011

x-30=1998

x=2028

Answer 2

b) x*a-x*b+9a-9b = 654 <=> x(a-b) + 9(a-b) = 654

x*6 + 9*6 = 654

6x + 54 = 654

6x = 654 - 54 = 600

x = 600/6 = 100

c) 7*a-7*b+x = 55 <=> 7(a-b)+x = 55

7*6 + x = 55

42 + x = 55

x = 55 - 42

x = 13

d) 13+x-(5*a-5*b) = 2011 <=> x-[5(a-b)] = 2011 - 13 = 1998

x-(5*6) = 1998

x - 30 = 1998

x = 1998 + 30

x = 2028