K = k + 1378
Cross multiply:
K * 8 = 7 * k + 13
Simplifying
K * 8 = 7 * k + 13
Reorder the terms for easier multiplication:
8K = 7 * k + 13
Reorder the terms:
8K = 7 * 13 + k
8K = 13 * 7 + k * 7
8K = 91 + 7k
Solving
8K = 91 + 7k
Solving for variable 'K'.
Move all terms containing K to the left, all other terms to the right.
Divide each side by '8'.
K = 11.375 + 0.875k
Simplifying
K = 11.375 + 0.875k
there it was hard but i got it
