Let's solve the following linear inequalities.
① 5x>x+21
② 2x+7≧9x+35
① First, in the same way as a linear equation, when calculated after moving the letter to the left side and the term with only numbers to the right side, it becomes 4x is greater than 28. Next, divide both sides by 4, the coefficient of x. Because 4 is a positive number, the direction of the inequality number does not change, and x is greater than 7.
x>7
② When rearranged, it becomes negative 7x is greater than or equal to 28. Divide both sides by negative 7, the coefficient of x. Because negative 7 is a negative number, the direction of the inequality sign is reversed, and x is less than or equal to negative 4.
x≦-4
|
|
|
|