Explain why one cannot add or subtract unlike terms. Use a simple example.?

Answer 1

because when they are unlike, the answer will be none of them. if you add 3desks with 4chairs, you will have 7 what?!?!?

Answer 2

"Unlike terms" means that the units of measure for each term are not the same...as is or as converted to other units if that is possible. There are only three fundamental units of measure: length (L), mass (M), and time (t). All the other units, like weight and velocity, are derived from the fundamental units.

Counts, as in the number of things, may also be included in the units of measure. But they are considered unitless; so counts can be mixed in with any of the three fundamental units. For example, when we say 6 seconds, the count is six and the units are seconds. 6 seconds actually means one second six times.

In the metric system (called SI), L is in meters, M is in kg, and time is in seconds. In the English system, L is in feet, M is in slugs, and time is in seconds. In units volume is indicated as L^3, which is the length unit cubed...as in 5 m^3. Area is shown as L^2...as is 10 ft^2.

I can add meters to feet because one converts readily to the other. One meter = about 3.3 feet. But I can't add meters to kilograms because they are not the same fundamental units of measure. They are L and M; like oil and water, they do not mix.

When an answerer uses apples and oranges as an example, he/she is not exactly correct. You can add/subtract the number of each; and the answer would be some number of apples and oranges (e.g., 25 apples and oranges in a sack). On the other hand, if you tried to add the size of an apple to the mass of that apple, you'd have a meaningless result. Size is a length measure (L^3 if size is given in volume) and mass is mass (M).

Unit analysis is a great way to check your math work. For example, F = ma; force equals mass (in M) times acceleration (a in L/sec^2). So if you get an answer for force that is not in ML/sec^2 units, you probably made a mistake. For instance, if your answer came out to be F = 5 kg-m/sec, youI probably incorrectly started with F = mv instead of = ma: where the units for v = .L/sec (velocity) and for a = L/sec^2 (acceleration).

A simple example: add 5 m^2 + 45 sec...can't makes no sense, that's because one term is in L^2 units and the other is in t units.

Answer 3

Unlike terms mean "different things." All that phrase is saying is that it doesn't make sense to try to subtract three apples from four oranges. It can't be done.

Answer 4

add 3 girls to one boy and what do you get?
lots of fun... yes you can add unlike terms...on my terms.

but you don't have any common result, still two groups.

Answer 5

Example: If you add 8g of cheese + 500ml of juice you remain with 8g of cheese + 500ml of juice [because they are not the same- unlike]
However if you subtract 3g of cheese from 8g of cheese + 500ml of juice = 5g of cheese + 500ml of juice.
The plus sign remains because you can not add cheese and juice together - they are unlike terms, BUT most importantly the unit of measurements are not "like" terms, i.e. grams and ml.
- You can however multiply them together
example, 9a x 2b = 18ab

Answer 6

its like trying to compare apples and oranges..

its just not the way it goes