how do u work out 5 - (3 + 2x)?
回答 (12)
✔ 最佳答案
Consider as:-
5 - 1 (3 + 2x)
5 - 3 - 2x
2 - 2x
= 5 - (3 + 2x)
= 5 - 3 - 2x
= 2 - 2x
5 - (3+2x)
1) Remove the grouping symbols by distributive property:
---> 5-3-2x
2) Combine "like-terms"
---> 2-2x
Answer: 2-2x
5 - (3 + 2x)
5 + (-1)(3 + 2x)
5 + -3+-2x
2 + -2x
2 = 2x
2/2 = 1
x = 1
This is an example of applying the distributive law to simplify an expression, but it may not be apparent at first.
Recall a(b+c) = ab + ac
Here you have a = 3, b = 2x, and the part you need to remember, the minus sign before the parenthesis means you have a = -1.
So 5 - (3+2x) = 5 - 3 -2x = 2 - 2x = 2(1-x)
5 - (3 + 2x)
= 5 - 3 - 2x
= 2 - 2x
Multiply Every thing inside the bracket with negative 1 and add to 5 ...
5-3-2x=2-2x
I am hoping that you are asking this question seriously and that you really are stuck and not just lazy.
First expand the bracket:
5 - 3 -2x.
Notice that the + turns into a -. Why? Well, try rewriting the original question in this way.
5 + (-1)(3+2x)
Now multiply the -1 into the bracket.
5+ (-3-2x)
Expand it and it becomes 5 - 3 -2x. You can do the rest. :D
To work out this problem, just perform the operation first within the parentheses and add similar values afterwards...
To do this,
Your equation says: 5 - (3 + 2x),
This can be rewritten in the form 5 - 3 - 2x. How come? The negative sign (-) preceeding the terms inside the parentheses constitute a negative 1 (-1) value, so performing the multiplication, a negative value multiplied with a positive (+) becomes negative (-).
-1 * (3 + 2x) = - 3 - 2x
thus, 5 - 3 - 2x
2 - 2x --------------->>> resulting equation
You can further simplify it by getting the common factor of both terms. The common factor is 2,
so your further resulting equation is,
2(1 - x) ------------------->>> Final Equation
You may want this final equation to equate it to zero (0) so that you can find for the value of x.
the form will become
2(1 - x) = 0
To get the value of x, you can do so by cross multiplication and transpose terms to either side. (Transpostion method is easier that adding/subtracting same terms to both sides of the equation. Just always remember that, if you transpose term to the other side, you change/reverse its sign!)
hence,
1 - x = 0/2
1 - x = 0
x = 1 ----------------------->>> Final Answer
收錄日期: 2021-05-01 10:05:55
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