By-cy 26m-39n 6s-8st 12ab square - 15asquareb 58.36+53.64. Do this too

The common factor is $y$.

$$
y(b - c)
$$
The factored expression is $\boxed{y(b - c)}$.

The factors of 26 are 1, 2, 13, 26.  
The factors of 39 are 1, 3, 13, 39.  
The GCD is 13.

$$
13(2m - 3n)
$$
The factored expression is $\boxed{13(2m - 3n)}$.

The common numerical factor (GCD of 6 and 8) is 2.  
The common variable factor is $s$.  
So, the common factor is $2s$.

$$
2s(3 - 4t)
$$
The factored expression is $\boxed{2s(3 - 4t)}$.

The common numerical factor (GCD of 12 and 15) is 3.  
The common variable factors are $a$ and $b$.  
So, the common factor is $3ab$.

$$
3ab(4b - 5a)
$$
The factored expression is $\boxed{3ab(4b - 5a)}$.

The common factor is 5.

$$
5(8.36 + 3.64)
$$

$$
5(12.00)
$$

$$
5 \times 12 = 60
$$
The simplified value is $\boxed{60}$.