Which line cuts the (y)-axis at ( (0,-10) ) and increases (y) by (28) when (x) increases by (4)?

Correct answer: \(y=7x-10\)

The slope is \(\frac{\Delta y}{\Delta x}=\frac{28}{4}=7\). The \(y\)-intercept is \(-10\), so in slope-intercept form \(y=mx+c\), substituting \(m=7\) and \(c=-10\) gives \(y=7x-10\). In \(y=28x-10\), the slope is 28, while in \(y=-7x-10\), \(y\) decreases as \(x\) increases. Exam tip: find slope by calculating \(\Delta y/\Delta x\).