Please, use " ^ " to denote exponentiation: x^2 + 4x - 21 = 0
Factor: (x+7)(x-3)=0
Solve for the 2 roots: x= -7 and x= 3: {3, -7} Note how this is in set notation.
50% of 36 means a half of 36 which is 18
Answer:

Step-by-step explanation:

Hope this helps.
Angle a is 22.62 degrees
and
angle b is 67.38 degrees
First, find the slope of the line. Use the two points given, (-4,0) and (4,2), in the slope formula rise over run. The change in rise is 2 and the change in run is 8, meaning that the slope is 2/8, simplified to 1/4. The y-intercept is 1, shown by the graph and the dashed line and shaded area means that the inequality symbol must be <. Slope-intercept form is shown as y = mx + b, so after putting our information in to the equation the answer is y < 1/4x + 1. Hope this helps!