Math problems absolute value problems help!! Urgent

1) Known |x-1|+|y-3|=0, find the value of x+y;

x-1|+|y-3|=0

x-1=-(y-3)

x-1)=y-3

x=y-3+1

x=y-2 (1)

x+1=y-3

x=y-3-1

x=y-4x=4-y (2)

There is (1) to bring in (2).

4-y=y-2

2y=6y=3 （3）

x=1 （4）

x+y=3+1=4

2) Known a 0, b 0, |a|＜|b|, simplify|a-b|-|a+b|.

a-b|-|a+b|

a+(-b)]-a+b|

a-b-[-a+b)]

a-b+a+b

2a can be tested by substitution: hypothesis a = 2, b = -3

The nucleus pose elimination with an absolute value less than 3 is.

The absolute value is not much changed to an integer known to 4.

Because the absolute value of x-3 + the absolute value of (3y+1) = 0, that is, x-3 = 03y + 1 = 0

So x=-3

y=-1/3

1) The distance from a=3 to (3,0) is 6, and the number represented by the dot is (-3,0) or (9,0).

2) If the sum of two non-negative numbers is 0, then both numbers are 0, i.e., x-9=0, x=9y-3=0, y=3

x+y+xy=12+27=39

3） |a|=2 and a is to the right of the origin of the number line, so a=2|c|=3 c is a little next to it, so c=3 (-3 is far from 2)|b|=2 and b is to the left of the origin, so b=-2

a+b+c=3

Reading the book several times and thinking more is much better than asking questions on the Internet

or -32.|x-9|+|y-3|=0, then x-9=0, y-3=0x=9, y=3

x+y+xy=9+3+9*3=39

3.By the title, got.

a=2,b=-2,c=3

So a+b+c=2-2+3=3

1, -3 or 9

2, x=9, y=3 so the original formula = 39

3 , a=2 b=-2 c=3 so the original formula = 3

1、d2、b

4. Sleepy spring <

5. D (but option a is not wrong for you to write Wang Bunai, it is a + b =2 a =2 b).

6、c7、c

8, b9, collapse <=0

4.-|1|Xiao Yin Zheng Yu -|

In the middle, the sail is late, and there is an equal sign.

The value of d a should be between 0 and 1 or between 0 and -1.

0y=4 so x+y=1

;;4.- Ranzen Zheng + big.

9 Question Dust Companion Sect is no problem, it is estimated that it should be a<=0

y>-3

So y+3>0

y+3|=y+3

y<2y-2<0

2y-4<0

So |y-2|=2-y

2y-4|=4-2y

So the original formula = (2-y) + (y + 3) - (3y + 9) - (4-2y) = 2-y + y + 3-3y - 9-4 + 2y

8-y

If the answer is 7km, then I think the problem should be that you only need to send it to A, B, and C stores, and if you need to go back to O, you have to go 10km, first from O to the north, and then to B, and then to the number of C, and finally to A,

On the number line, the absolute value of a number represents the distance (from the origin), and the farther away from the origin, the greater the absolute value. Since the distance is always positive and 0, the absolute value of a rational number cannot be (negative), that is, a takes any rational number, and there is 丨a丨( )0

Rational numbers whose absolute value is equal to the same integer have (0,1) and they (absolute value equal to themselves).

I don't know if that's right!

1 The absolute value of a number represents the distance (from the number to the origin)2 The farther away from the origin, the absolute value (the smaller).

3 then the absolute value of a rational number cannot be (is a negative number), and 4 has 丨a丨 (greater than or equal to) 0

The last empty is incomprehensible.

This counts to the origin.

The greater the negative number. Greater than or equal to.

Both positive and absolute values of 0 are equal to themselves.

1.A number of distances to the origin2The bigger the 3Negative number 4Greater than or equal to.

Distance from the origin.

The greater the negative number. Greater than or equal to.

I don't know about the back 2.