How do you decrease 2796 by 25%?
And how do you increase 1256 by 50%?

1.)   2097

2.)  3768

Step-by-step explanation:

1.)   2796 times 0.25 = 699

      2796 - 699 = 2097

2.)   1256/0.5 = 2512

      1256 + 2512 = 3768

the sum of all the angles in a triangle are equal to 180

so you can add   the 3 given angles together to equal 180:

5y + 2y + 2y = 180

or since all three angles have the same letter, combine the 3 angles to equal 180:

9y = 180