Question

What is the solution to the inequality: 7 - 8x < -x + 28

Answer 1

$7-8x < -x+28\\7-8x < 28-x\\7-28 < 8x - x\\-21 < 7x\\-3 < x$

(Sorry fo the graph) The idea is the following, draw the straigh line, and put the numbers -3, -2 ,-1, 0, 1, etc. In the position -3 you need to start to draw the interval solution, with an open circle.

$(-3, \infty)$

It is like $\hspace{0.4cm} \circ ----------\\-3 , -2, 0, 1 , 2, ...$