Answer:

Step-by-step explanation:
we know that
The surface area of the regular pyramid is equal to the area of the triangular base plus the area of its three triangular lateral faces
step 1
Find the area of the triangular base
we know that
The triangular base is an equilateral triangle
so
The area applying the law of sines is equal to


step 2
Find the area of its three triangular lateral faces
![A=3[\frac{1}{2}bh]](https://tex.z-dn.net/?f=A%3D3%5B%5Cfrac%7B1%7D%7B2%7Dbh%5D)
we have

Find the height of triangles
Applying the Pythagorean Theorem

solve for h



substitute

step 3
Find the surface area
Adds the areas

Round to the nearest tenth

Answer:
8 cm
Step-by-step explanation:
the 3 cm line from the chord to the center of a circle is a leg of a right triangle which perpendicularly bisects the chord into two equal halves
draw the hypotenuse of the right triangle from the center of the circle to the endpoint of the chord. This is a radius measuring 5 cm.
find the missing leg of the right triangle
a^2= c^2- b^2
a^2= 25-9
a^2=16
a=4
this is only the measurement of half the chord. To find the full length of the chord multiply by two
4*2=8 cm
Answer:
AS IT IS RIGHT ANGLE .
THEREFORE, 1 ANGLE =90°
A=55°,
LET LAST ANGLE BE Y.
THEREFORE, Y=90-55=35°
RATIO OF A:Y=55:35=11/7
RATIO OF ANÔTHER SIDE :X=11:7
HYPOTENOUES=8
THEREFORE8^2=11X^2+7X^2
64=121X^2+49X
Answer:
x=-5 or -5
Step-by-step explanation:
x - 4 = 2x + 1
Subtract x from both sides canceling out the x on the left, getting...
-4 = x + 1
Then subtract the 1 from both sides canceling out the 1 on the right, getting...
-5 = x
Subtracting x from 2x gets you 1x which you just write as x because there is only one x. Doing the equation from the other side will still get you the same answer and I will show you.
x - 4 = 2x + 1
-x - 4 = 1
-x = 5
x = -5
Hope this helps!
Answer:
1. 7.6 = c
2. 45 = c
Step-by-step explanation:
1. 3^2 + 7^2 = c^2
9 + 49 = c^2
58 = c^2
square root both sides = 7.6 = c
2. 27^2 + 36^2 = c^2
729 + 1296 = c^2
2025 = c^2
square root both sides
c = 45