Answer:

Step-by-step explanation:
we have

step 1
Eliminate the parenthesis

The symbol of the term 3x is incorrect, must be positive instead of negative
so

Group terms that contain the same variable

Combine like terms

5 would be the dependent variable because the number 5 depends on how many greeting cards are bought.
Answer:
When you say that, I think directly to Triangles. SO i am going to state that.
There is acute: Less than 90 degrees
There is Obtuse: more than 90 degrees
There is Right: 90 degrees
Your best bet would be to google it dog
Answer:
137.4 meters
Step-by-step explanation:
In this case, they give us the height of the lighthouse that corresponds to 50 meters and the depression angle is 20 °, in this case we can apply the tangent trigonometric function, which relates the opposite side to the adjacent side.
tan a ° = opposite / adjacent
the horizontal that is formed would be the adjacent side, therefore if we solve we are left with:
horizontal distance = opposite / tan to °
replacing, we are left with:
hd = 50 / tan 20 °
hd = 50 / 0.3639
hd = 137.4
the horizontal distance is equal to 137.4 meters