Answer:
18
Step-by-step explanation:
21-n; n=3
Substitute n for 3:
Solve.
Angles B and D are supplementary angles, so if B's angle is 30 degrees, then D's angle at y would be 150, since they have to add to 180.
In short, angle y = 150
Step-by-step explanation:

Hope it will help :)
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F(x) is the same as y. so you’d choose two coordinates and do y2-y1 over x2-x1. id recommend doing that with whole numbers, no decimals. by doing that you get your slope.