Solve for a and b: Algebra Equations a^2+a^2=200, a+b=30

Published on April 9, 2026

Algebra

Solve the system of two algebraic equations to find the values of a and b, and then calculate the ratio b/a.

Question

Answer

We are given the following equations:
  1. We need to find the value of .
Let’s solve the first equation for :


Divide both sides by 2:


Take the square root of both sides:

Now we have two possible values for : or .
Case 1:
Substitute into the second equation, :

Subtract 10 from both sides:


Now, calculate :
Case 2:
Substitute into the second equation, :

Add 10 to both sides:


Now, calculate :
Since the problem does not specify whether is positive or negative, there are two possible answers. However, in many contexts where such problems are presented without further constraints, a positive value for variables is often implied, or the simplest positive solution is preferred. If we consider the visual representation, the numbers are written with white chalk on a green board, and there are no explicit constraints that would force us to choose a negative value. Therefore, we will present both possible answers.
The final answer is .

Theorems

• Square Root Property

If , then or .

• Substitution Property of Equality

If , then can be replaced by in any expression or equation.

• Division Property of Equality

If and , then .