Consider two congruent triangular prisms. Each rectangular face of prism A has a width of x + 2 and each rectangular face of prism B has a length of 2x + 1. If each rectangular face of prism A has an area of 5x + 10, what is the volume of prism B? (round to nearest whole number in cm3)

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Answer:

[tex]20\sqrt{3}[/tex]

Step-by-step explanation:

Width of rectangular face of  prism A = x+2

Area of rectangular face of prism A = 5x+10

So, length of rectangular face of prism A = [tex]\frac{Area}{Width} =\frac{5x+10}{x+2} =5[/tex]

Now , the length of rectangular face of prism B is 2x+1

Since we are given that the prisms are congruent

So, Length of rectangular face of both prisms must be equal

So, [tex]2x+1=5[/tex]

[tex]2x=4[/tex]

[tex]x=2[/tex]

So,the length of rectangular face of prism B = 2x+1 = (2*2)+1=5

Thus the height of prism = 5 cm

Volume of prism = [tex]\text{Area of equilateral triangle} \times Height[/tex]

                            = [tex]\frac{\sqrt{3}}{4} a^2 \times Height[/tex]

Where a is the side of triangle

Side of triangle = width = x+2=2+2=4

So, Volume of prism = [tex]\frac{\sqrt{3}}{4} a^2 \times Height[/tex]

                                   = [tex]\frac{\sqrt{3}}{4} (4)^2 \times 5[/tex]

                                   =[tex]20\sqrt{3}[/tex]

Hence the volume of prism is    [tex]20\sqrt{3}[/tex]