una dintre fetele laterale ale unei piramide patrulatere regulate este triunghi echilateral cu latura de 7cm. Calculati aria bazei piramidei consideratei

21.27 cm^2

Step-by-step explanation:

Pentru a calcula aria bazei, putem folosi formula lui Heron Matematic aceasta este;

A = √s (s-a) (s-b) (s-c)

Unde s = (a + b + c) / 2

a, b, c se referă la laturile triunghiului

A = (7 + 7 + 7) / 2 = 21/2 = 10,5

A = √10,5 (10,5-7) (10,5-7) (10,5-7)

A = √10,5 (3,5) (3,5) (3,5)

A = √450.1875

A = 21.2176 cm ^ 2, care este de aproximativ

21.22 cm ^ 2

-3

step-by-step explanation:

a drawing really does here:

so i draw the horizontal line y=2 and the vertical line x=-2 at this intersection i put b (this is where my right angle is going to be).   so point b is at (-2,2).   point a is 5 units long and is also on y=2 so this point has to be (3,2) or (-7,2) -doesn't matter i will go with (3,2).

now we know c is at (-2,y) we don't know the y yet bet we know that c is on x=-2.

we have the area of the triangle is .5bh=12.5

we know the base length is 5 (ab)

we have the height is (2-y) if you look at your

plug in

.5(5)(2-y)=12.5

solve for y to get the y-coordinate for c

2.5(2-y)=12.5

divide both sides by 2.5 giving:

2-y=5

now subtract 2 on both sides

-y=3

y=-3

nada

step-by-step explanation: