Step-by-step explanation:
denominators showing all working <3
<u>Given</u>:
The length of DE is 8 cm and the measure of ∠ADE is 60°.
We need to determine the surface area of the pyramid.
<u>Length of AD:</u>
The length of AD is given by


Length of AD = 8 cm
<u>Slant height:</u>
The slant height EF can be determined using the trigonometric ratio.
Thus, we have;




Thus, the slant height EF is 4√3
<u>Surface area of the square pyramid:</u>
The surface area of the square pyramid can be determined using the formula,

Substituting the values, we have;




The exact form of the area of the square pyramid is 
Substituting √3 = 1.732 in the above expression, we have;


Rounding off to one decimal place, we get;

Thus, the area of the square pyramid is 174.8 cm²
When a question is asking you for the y-intercept based on a graph, all you have to do is look to see at what point does the function cross/intersect the y-axis. The x-value will always be zero in a y-intercept. By looking at the graph you see that the function crosses the y-axis at the point (0, -1), which is your answer.
Answer: (0, -1)
There you go!! Hope it helps