Alina is building a roof for a dog house. She uses plywood to make the roof with the dimensions shown, but with an open bottom. A net of a square pyramid has a square base with side lengths of 4 feet, and 4 triangular sides with heights of 3 feet.

How many faces will she need to consider when deciding the amount of shingles to buy for the roof?

faces

4 FACES!

Step-by-step explanation:

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Step-by-step explanation:

Alina is building a roof for a dog house with the dimensions shown. She uses plywood to make the roof with the dimensions shown, but with an open bottom.

A net of a square pyramid has a square base with side lengths of 4 feet, and 4 triangular sides with heights of 3 feet.

Find the surface area of the roof.

The area of each triangular face is  

✔ 6

ft2.

The surface area of the roof is  

✔ 24

ft2.

(0,-3) see attached graph

step-by-step explanation:

a. to solve the system, graph the two equations.

x = y+3 becomes y=x-3 has m=1/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move up 1 unit and 1 unit to the right. plot a point and connect.

y=-4x+3 has m =-4/1 and b=-3. start at (0,-3) on the y-axis and plot a point. then move down four units and to the right 1 unit. plot a point and connect.

the solution is the point (x,y) where the two lines intersect. by the graph below it is (0,-3).

b. to solve by substitution, substitute y = -4x-3 into x= y+3

x= (-4x-3) +3

x=-4x

5x=0

x=0

now substitute x = 0 back in to find y.

y= -4(0)-3

y=0-3

y=-3

solution is (0,-3)

c. use elimination by adding the equations together.

x-y=3

4x+y=-3

5x=0

x=0

then substitute into one equation to find y.

y=-4(0)-3

y=-3

the correct answer is d

hope this