SURFACE AREA OF PRISM-TRAPEZIUM HI guys I am going to show to you a phenomenal

and fantastic way to find the phases of this trapezium prism, what I am talking the surface

area, another words the space all over each individual exterior phase that is why we are

going to work out. Now this trapezium prism that is going to has 6 phase and we are going

to do it in five simple and straight forward steps. And now in order to work this out first

of all we are going a need to find the front phase first why? Because that is the trapezium

part is, see that trapezium parallel lines and two lines coming from out there we do

have vertical height perpendicular right there. So let us go to step no. 1, now before we

do that, all unit are all in meter, so the answer is going to be in meter squared so

let us find out the full scope of the entire space all over the skin of this trapezium

prism. Step no. 1, as I said earlier is to work out the phase this front one here is

a trapezium, let us work that out. So the formula for the area of a trapezium is, if

you do not recall it, you may want to revise it from the other chapter but feel free to

watch now as I go through it to lots of detail for you. So I got a ½ x the height, the height

has to be perpendicular height , there is that perpendicular height there happens to

be 5m. and the a + b are the two parallel lines top and bottom we got 10m across here

so that 10, that is also 10 there yeah can you see that? That is 1o equal because that

is 10 and the bottom here, the base we have 14m so that is going to have a and b respectively

so, let us plug in drag in drop those numbers into formula we can work out the trapezium

area of the front phase, by the way if the front phase comes to a certain amount the

back phase would be exactly the same. So let us work that out, vertical height 5 a across

here is 10, and b the base is 14. Ok let us point in our calculators, so it is going to

be a ½ x 5 times which is 2.5 times 10 + 14, 10 + 14 is 24, so multiplying all that

three out the area of the front phase all together in your calculator and is going to

yield 60m squared, ok that is the front phase which means that back phase is going to be

also 60m square let us put area back. Ok this is the area of the back we got the front and

the back and now where we goes to the right side of the phase, and the right side of the

phase is right over there you can see the slant length over there is 6 and the dept

is 7 all we need to do now length times breth and we will that out simple area of that breath

rectangle right there 6×7 is 42 so right side of the phase, area of the right equals 6×7

which equal 42m squared so there is the right side, now the right side is 42, the left side

guess what? The left side because it is symmetrical is exactly the same it is that also going

to be 42, so area left is equal to 42m squared, so we got the front we got the back, we got

the right, we got the left. Now let us work the area right at the top up there, what is

that area? So what is going to be 10 across there time the depth there is going to be

10 times the dept is written like this, 7 there, that is also 7 there so 1o x 7, that

is going to give us 70 so that is top phase there, area of top, now if the area of the

top is 70m squared, is the area of the bottom? Is no, let us have a look here, the bottom

is 14 across there and the depth is 7 across there so that is going to be 14×7 so area

for b, b for bottom=14×7 and that yields a total of 14×7 that is 98m squared and now

we have work out 6 phases, let us check if we got 6, one, two, three, four, five, and

six therefore we have all 6 phases all we have to do now is add them all together to

get the complete space surface space of this trapezium prism, so let us add them all together.

So, we have the two 60’s which are the areas of the front phase and the back phase, write

that up, and then we have the two 42’s which are the right and the left phase and then

we have finally the top which is up there which is 70 and the bottom under there 14×7

which is 98, ok, let us get our calculators out so we can work out the total, complete

and scope and size of skin and the exterior outside surface of this trapezium prism. In

our calculator 60+60+42+42+70+98 grand total, altogether the entire total complete surface

area is 372m squared. Take a minute to check out our website at

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