Given the formula p= 2a + b rearrange the equation to isolate for a

a = (p - b)/2

Step-by-step explanation:

Isolate the variable, a. Note the equal sign, what you do to one side, you do to the other. Do the opposite of PEMDAS.

PEMDAS is the order of operation, and  =

Parenthesis

Exponents (& roots)

Multiplication

Division

Addition

Subtraction

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First, subtract b from both sides:

p (-b) = 2a + b (-b)

p - b = 2a

2a = p - b

Next, divide 2 from both sides:

(2a)/2 = (p - b)/2

a = (p - b)/2

a = (p - b)/2 is your answer.

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a = (p + b) / 2

Step-by-step explanation:

p = 2a + b

2a - b = p

+b

2a = p + b

/ 2

a = p + b

a = (p + b) / 2

439400

step-by-step explanation:

130^2 = 16900

16900*26 = 439400

56.6

step-by-step explanation:

the ratio of the perimeters is equal to the scale.

the ratio of the areas is equal to the square of the scale.

34 / 20 = k

a / 19.6 = k²

substituting:

a / 19.6 = (34 / 20)²

a = 19.6 (34 / 20)²

a ≈ 56.6