X^2 - 6x = 20
x^2 - 6x + 9 = 20 + 9
(x - 3)^2 = 29
x - 3 = (+-) sqrt 29
x = 3 (+-) sqrt 29
x = 3 (+-) 5.39
x = 3 + 5.39 = 8.39 <=
x = 3 - 5.39 = - 2.39 <=
Use the calculator to find:
169^2=169*169=28561
That is called a constant
like 2,3,234234, -903
it doesn't have a placeholder
Gcf refers to a digit which can divide both numbers without a remainder
20|50 is divisible by 2 to become 10|25 and then divisible by 5 to become 2|5
=2×5
Gcf= 10
