What would the algebraic expression be for the product of 3 and x increased by 20

C.)  11r² + 8

Step-by-step explanation:

Perimeter is the distance around a shape.

So to find the perimeter, add the lengths of each side:

P = r² + 3 + r² + 4 + 5r² + 2 + 4r² - 1

Solve by addition:

Let's add the whole numbers first:

P = r² + 3 + r² + 4 + 5r² + 2 + 4r² - 1

P = 8 +  r² + r² + 5r² + 4r²

Let's add the other terms:

P = 8 +  r² + r² + 5r² + 4r²

P = 8 + 11r²

Write in standard form:

P = 11r² + 8