Question

determine os valores de x e y nos seguintes feixes de paralelas

Answer 1

a) 21÷(2+5) = x÷2
21÷7 = x÷2
3 = x÷2
3×2 = x
x = 6

21÷7 = y÷5
3 = y÷5
3×5 = y
y = 15

b) x÷2,5 = 8÷4
x÷2,5 = 2
x = 2,5×2
x = 5

y÷6 = 4÷8
y÷6 = 0,5
y = 0,5×6
y = 3

c) 20÷(6+4) = x÷6
20÷10 = x÷6
2 = x÷6
2×6 = x
x = 12

20÷10 = y÷4
2 = y÷4
2×4 = y
y = 8

d) (x+2)÷12 = x÷9
(x+2)×9 = x×12
9x + 18 = 12x
18 = 12x - 9x
18 = 3x
18÷3 = x
x = 6