Question

Sttind ca a+b =11, determinati numarul x din:a) 8 x a + x + 8 *b=93
b)5*x + 4 * a + 3* b =85 - 2 * b-a
c)a + x * b + x * a + b = 132
PRIMUL CARE RASPUNDE PRIMESTE COROANA

Answer 1

8a+x+8b=93
8a+8b+x=93
8(a+b)+x=93
x=5

5x+4a+3b=85-2b-a
5x+4a+a+3b+2b=85
5x+5a+5b=85
5x+5(a+b)=85
5x+5*11=85
x=6

a+xb+ax+b=132
a+b+x(a+b)=132
(a+b)(1+x)=132
11*(1+x)=132
1+x=12
x=11

Answer 2

a+b=11

a)
8 x a + X + 8 *b=93
8 × (a+b) + X = 93
8 × 11 + X=93
88 + X=93
X = 93 - 88
X = 5


b)
5*x + 4 * a + 3* b =85 - 2 * b-a
5*x + 4 * a + 3* b+ 2 * b + a =85
5*x + 5 * a + 5 * b = 85
5*x + 5 * (a + b) = 85
5*x + 5 * 11 = 85
5*x + 55 = 85
5*x = 85 - 55
5*x = 30
x= 30 : 5
x = 6


c)
a + x * b + x * a + b = 132
a + b + X * (a + b ) = 132
11 + X * 11 = 132
X * 11 = 132 -11
X * 11 = 121
X = 121 : 11
X = 11