Question

I’m very confused on this problem and need some clarity

Answer 1

Given the question in the image, the following are the solution steps to answer the question

STEP 1: Write the formula for finding the perimeter of a triangle

`\begin{gathered} \text{Perimeter of a triangle is the sum of all the sides of the triangle} \\ \text{That is: }a+b+c_{} \\ \text{where a,b and c are the sides} \end{gathered}`

STEP 2: Write the given sides

`\begin{gathered} \text{Let a=7.3}cm \\ \text{Let b=2.94}cm \\ \text{Let c=unknown}=x \\ \text{Perimeter}=14.8cm \end{gathered}`

STEP 3: Substitute the values into the formula

`\begin{gathered} \text{Perimer}=a+b+c_{} \\ 14.8=7.3+2.94+x---equation\text{ 1} \\ By\text{ subtracting x from both sides} \\ 14.8-x=7.3+2.94+x-x \\ 14.8-x=7.3+2.94----\text{equation 2} \\ U\sin g\text{ equation 1 again,} \\ 14.8=7.3+2.94+x \\ 14.8=10.24+x \\ 14.8=x+10.24-----equation\text{ 3} \end{gathered}`

STEP 4: Choose the equation that could not be used to find the third side

The equation in option B can be seen in equation 1 in Step 3

The equation in option C can be seen in equation 3 in Step 3

The equation in option D can be seen in equation 2 in Step 3

Hence, the equation that could not be used to find the third side is the equation in option A

x - 14.8 = 2.94 + 7.3