Find the sum of -3a and 5a -3
-3a + (5a-3)
2a-3
We have these opposite pairs
- 9.2 and -9.2
- 2.9 and -2.9
- 1.4 and -1.4
- 4.1 and -4.1
So all we're doing is matching each positive number with its negative version. In terms of a visual, the opposite of a number is mirrored over 0 on the number line. So for instance, the opposite of 2 is -2, with each being two units away from 0 on the number line.
Yes, 3/4 is bigger than 3/5.
One way you can verify this is by drawing a bar model, and cut it into four. Color in three pieces.
Then, draw another bar model the same size as the first one, and cut it into five pieces.
Color in three pieces.
You can see that 3/4 has more shaded in area than 3/5.
Another way you can do this is by dividing the numerator by the denominator for both fractions.
Hope this helped.