math (surface area)

posted by .

i know the formula of a rectangles surface area is SA= 2(lw)+(wh)+(lh), but when the dimensions are : 2a for the height, a for the width, and 3a for the length, how do i solve?

  • math (surface area) -

    Put l=3a, w=a, h=2a
    into your formula to get
    S = 2(lw+wh+lh)
    = 2(3a*a + a*2a + 3a*2a)
    = 2(11a²)
    = 22a²

    Check my work.

    Bote: The parentheses in your formula have been misplaced. The correct form is:
    S=2(lw+wh+lh)

  • math (surface area) -

    I have no clue I suck at math can someone PLEASE help me to!??!

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. math

    Recognize that rectangles that have the same area can have different perimenters. Do rectangles with the same area necessarily have the same perimeter?
  2. math

    Find the lateral and surface area of the right rectangular prism whose length is 7 cm, width is 5 cm, and height is 1.5 cm. I think the answer is 36 for lateral area and 106 as surface area. I made a formula, 2(7 x 1.5 + 1.5 x 5)) …
  3. algebra

    sooo confusing... 6. (¼ + 7/8)(9/13) A81/13 B17/104 C81/104 D17/29 E17/13 F17/25 7. [6(2+1) -6(1+1)] / [6(4-2) - 22 ] A3/2 B3/4 C3/5 D3 E1/3 F2/3 8. -3(y – 5) - (-2y + 1) A-y +14 B5y - 4 C-5y + 14 D-13y E-5y -6 F-y – 4 For problems …
  4. MATH-Stuck

    For each of the following, the Surface Area is given. Calculate the missing dimension. This is a rectangular prism with the width missing. The height seems to be 20 cm. The length I guess is 34 cm, and the Surface Area is 6020cm square. …
  5. geometry

    The lateral area of a prism is 144cm^2 (lateral area is surface area without the bases). If the height is double the width, and the length is triple the width, what is the surface area?
  6. Math

    A rectangular prism has a volume of 960cm. It's width, length, and height are in the ratio 3:5:8. A) Determine the dimensions of the prism B) What is the ratio of the left side to the front to the top of the prism by surface area?
  7. Math

    Find the surface area of rectangular pyramids 1. Length= 1.15ft Width=0.82 ft Height of the slanted face =3.17ft Surface Area=7.1879ft^2 Formula for Rectangular Pyramid Surface Area : B+1/2pl B=area of base p=perimeter of base l=height …
  8. math( surface area)

    write a product that represents the surface area of any rectangular prism with length l, width w, and height h. Expain.
  9. Geometry

    What is the lateral surface area of the prism?
  10. Math

    3. All faces of a table top with the given dimensions (width:20, length:22, height:1)are going to be painted. Which of the following is the surface area of the table top?

More Similar Questions