# Find the value of one expression from another

The value of $$17x + 51y$$ is 85. What is the value of $$19x + 57y?$$

What I notice right away is that 19/17 = 57/51. Thus, to find the value of $$19x + 57y,$$ I need to scale 85 by 19/17. $$\dfrac{85 \cdot 19}{17} = \dfrac{5 \cdot 17 \cdot 19}{17} = 5 \cdot 19 = 95$$