4x-5y=3
4x-5(10)=3
4x-50=3
+50 +50
4x=53
/4 /4
x=53/4
38/14= 2 10/14= 2 5/7
The answer is 2 5/7
1. Perfect square trinomials, are 2nd degree polynomials, of the form

so that

, which can be written as perfect squares.
2. For example

3. Thus

are perfect square trinomials.
4.

5. In the first case -b=20, so b=-20. In the second case, -b=-20, so b=20.
6. b∈{-20, 20}