Question

Which equation can be used to find the value of “b” if side “a” measures 8.7 cm?

Answer 1

Answer:

D. $34.8+b=54.6$

Step-by-step explanation:

We have been given an image of a scalene triangle. We are asked to find the equation that  can be used to find the value of “b".

We know that perimeter of a triangle is sum of three side lengths of the triangle.

Upon adding the measure of side lengths for our given triangle, we will get:

$\text{Perimeter}=a+3a+b$

Combining like terms we will get,

$\text{Perimeter}=4a+b$

Substituting the value of perimeter and 'a' in above equation we will get:

$54.6=4\times 8.7+b$

$54.6=34.8+b$

$34.8+b=54.6$

Upon looking at our given choices, we can see that option D is the correct choice.

Answer 2

Answer:

Option D) b + 34.8 = 54.6 is the equation can be used to find the value of b.      

Step-by-step explanation:

We are given the following information in the question:

Perimeter of scalene triangle = 54.6 cm

The sides of triangle given are b, a and 3a.

Thus, we can write that:

$\text{Perimeter of Triangle = Side 1 + Side 2 + Side 3} = b + a + 3a = 54.6~cm$

We are given that a  = 8.7 cm

Putting this value, we have:

$b + a + 3a = 54.6~cm\\b + 8.7 + 3(8.7) = 54.6\\b + 8.7 + 26.1 = 54.6\\b + 34.8 = 54.6\\b = 54.6 - 34.8\\b = 19.8~cm$

Thus, Option D) b + 34.8 = 54.6 is the equation can be used to find the value of b.