Dea writes the expression 0.25 + 0.76 + 0.75 + 0.24. she rewrites the expression using the commutative property. which expression could dea have written using the commutative property?
a) (0.25 + 0.76) + (0.75 + 0.24)
b) 0.25 + 0.75 + 0.76 + 0.24
c) (0.25 + 0.76) − (0.75 + 0.24)
d) 0.25(1 + 1)

B )  0.25 + 0.75 + 0.76 + 0.24

Step-by-step explanation:

commutative law of addition:-

According to the commutative property of addition,changing the order of the numbers.we are adding doesn't change the sum.

let a,b,c+d are two numbers

The commutative property condition in addition a+b+c+d = a+c+b+d

Given expression 0.25+0.76+0.75+0.24 = 0.25 + 0.75 + 0.76 + 0.24

conclusion:-  Answer B.

{x = -1/2 ,   y = -1

step-by-step explanation:

solve the following system:

{2 x + y = -2

{10 x - 3 y = -2

in the first equation, look to solve for y:

{2 x + y = -2

{10 x - 3 y = -2

subtract 2 x from both sides:

{y = -2 x - 2

{10 x - 3 y = -2

substitute y = -2 x - 2 into the second equation:

{y = -2 x - 2

{10 x - 3 (-2 x - 2) = -2

10 x - 3 (-2 x - 2) = (6 x + 6) + 10 x = 16 x + 6:

{y = -2 x - 2

{16 x + 6 = -2

in the second equation, look to solve for x:

{y = -2 x - 2

{16 x + 6 = -2

subtract 6 from both sides:

{y = -2 x - 2

{16 x = -8

divide both sides by 16:

{y = -2 x - 2

{x = -1/2

substitute x = -1/2 into the first equation:

{y = -1

{x = -1/2

collect results in alphabetical order:

answer:   {x = -1/2 ,   y = -1

make sure you have version 2.50

try looking in the very back of the book : )

step-by-step explanation:

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