Question

For each shape, write an algebraic expression for its perimeter - part A and B

Answer 1

Answer:

a)  p + q + r

b)  2(a + b)

Step-by-step explanation:

The perimeter of a two-dimensional shape is the distance all the way around the outside.

An algebraic expression contains one or more numbers, variables, and arithmetic operations.

A variable is a symbol (usually a letter) that represents an unknown numerical value in an equation or expression.

Question (a)

The length of each side of the triangle is labeled p, q and r.  Therefore, the perimeter is the sum of the sides:

Perimeter = p + q + r

So the algebraic expression for the perimeter of the triangle is:

p + q + r

Question (b)

Not all of the sides of the shape have been labeled.  

However, note that the horizontal length labeled "a" is equal to the sum of "c" and the horizontal length with no label.

Similarly, note that the vertical length labeled "b" is equal to the sum of "d" and the vertical length with no label.

Therefore, the perimeter is twice the sum of a and b:

Perimeter = 2(a + b)

So the algebraic expression for the perimeter of the shape is:

2(a + b)