Regular triangular pyramid has the slant height k=12 cm and lateral area al = 198 cm2. find the length of the base edge.

To solve this we are going to use the formula for the lateral surface area of a regular pyramid: 
where 
is the lateral surface area.
is the perimeter of the base.
is the slant height.

We know for our problem that  and , so lets replace those values in our formula and solve for :






Now we know that the perimeter of the base of our regular triangular pyramid is 33 cm. Remember that the perimeter of a triangle is the sum of its 3 sides. Since our pyramid is regular, its base will be an equilateral triangle, so to find the length of the base edge, we just need to divide the perimeter by 3:



We can conclude that the length of the base edge of our regular triangular pyramid is 11 cm.

0=6x+2y+10 is equivalent to the simplified form: y= -3x - 5• parallel lines always have the same slope, different y intercept knowing this, we can say the slope, or m of the line parallel to y= -3x - 5 is -3.m= -3 hope this could !