The equation for the area of a triangle is A= b*h /2. So, plug in your known variables, and you get 270in^2= b*30 /2. First you multiply by 2 to cancel out the division for 2, which gets you 540= b* 30. To get "b" by itself, divide both sides by 30, giving you <u>18=b</u>.
To check this, plug in your new known variable, as 270= 18* 30 /2. This will equal as 270=270, confirming 18in as the correct measurement.
Answer:
72
Step-by-step explanation:
Well to make life easier just simplify the fraction
80/100 could be simplified to 4/5
4/5*90 is 72
Given:
A prism with height 5 cm and equilateral triangular base with side 2 cm.
To find:
The total surface area of the prism.
Solution:
Area of an equilateral triangle is:

Where, a is the side length.
Putting
, we get




The base and top of the prism are congruent so their area must be equal.
The lateral surface area of the prism is:

Where, P is the perimeter of the base and h is the height of the prism.
The lateral surface area of the prism is:



Now, the total surface area is the sum of areas of bases and lateral surface area.




Therefore, the total surface area is 33.46 cm².