The sum of three fourths of a number and 1 is 5

Do you need to solve for "a number"? 

Let's call it x. So (3/4)x + 1 = 5.
Subtract 1 from both sides because we want to separate that x from everything else. 

(3/4)x = 4.

Multiply both sides by 4.
3x = 16.

Divide both sides by 3. x = 16/3.

To test it, (16/3)(3/4) + 1
(48/12) + 1
4 + 1
5

A quadratic polynomial has a degree of two