Find the height of a rectangular prism if the surface area is 458.17in^2, the width is 6.2in and the length is 8.3in.
Find the surface area of all the sides with a width and length first can you do that?
? hello?
@Icedragon50 trying to figure out if i can lol
ok
@Icedragon50 just got one surface area, 8.3(6.2)=51.46
well heres a hint: two sides have an area of width * length
@Icedragon50 yeah i did that and got 51.46 lol
Very good! now since theres TWO sides so multiply by 2 to get:102.96
102.92 srry
@Icedragon50 aaah okay so what's next?
Ok so now we have 4 more faces. 2 of them are width*height and length*height
width*Height would be 6.2*h=6.2h
length*height would be 8.3*h=8.3h
now you solve for h (height) by using this equation: 102.92+6.2h+8.3h=458.17
@Icedragon50 h=24.5?
102.92+14.5h=458.17 14.5h=458.17-102.92 14.5h=355.25 h=24.5 So, height is 24.5
yes lol
@Icedragon50 that isn't any of my options :(
wit are your options??
@Icedragon50 10.25 12.25 14.25 16.25
:O
hmmm gimmee a sec
do you know what surface area is?
first, draw a rectangular prism and see if you can better visualize the problem
@nincompoop i did on my paper
draw it here
OK THIS TOOK ME FOREVER BUT HERE IT IS
SA = Surface Area = 458.17 in² L = Length = 8.3 in W = Width = 6.2 in H = Height = What we're solving for. The formula for the surface area of a rectangular prism is SA = 2*(LW + LH + WH) Substituting values: 458.17 = 2*(8.3*6.2 + 8.3H + 6.2H) 229.085 = 51.46 + 14.5H 14.5H = 229.085 - 51.46 H = 117.625/14.5 H = 12.25 inches. That's about it! =)
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