Question

Find the area, in square feet, of a triangle whose base is 42⁄3 feet and whose altitude is 84⁄7 feet. A. 135⁄21 B. 20 C. 40 D. 2610⁄21

Answer 1

Answer: B. 20

Explanation:

Hi to answer this question we have to apply the next formula:

Area of a triangle: base x height (altitude) x 1/2

Replacing with the values given:

A =4 2/3 x 8 4/7 x 1/2

A= (4x3+2)/3 x (8x7+4)/7 x 1/2

A = 14/3 x 60/7 x 1/2 = 840/42=20 square feet

So, the correct option is B.20

Feel free to ask for more if needed or if you did not understand something.

Answer 2

Option B.
`20\ ft^(2)`

Explanation:

we know that

The area of a triangle is equal to

`A=(1)/(2)bh`

we have

`b=4(2)/(3)\ ft`

`h=8(4)/(7)\ ft`

Convert mixed numbers to an improper fractions

`b=4(2)/(3)\ ft=(4*3+2)/(3)=(14)/(3)\ ft`

`h=8(4)/(7)\ ft=(8*7+4)/(7)=(60)/(7)\ ft`

substitute the values

`A=(1)/(2)((14)/(3))((60)/(7))\\ \\A=(14*60)/(2*3*7)\\ \\A=(840)/(42) \\ \\A=20\ ft^(2)`