# Write as a Function of y y = square root of 49-x^2

Rewrite the equation as .
To remove the radical on the left side of the equation, square both sides of the equation.
Simplify each side of the equation.
Multiply the exponents in .
Apply the power rule and multiply exponents, .
Cancel the common factor of .
Cancel the common factor.
Rewrite the expression.
Simplify.
Solve for .
Subtract from both sides of the equation.
Multiply each term in by
Multiply each term in by .
Multiply .
Multiply by .
Multiply by .
Simplify each term.
Move to the left of .
Rewrite as .
Multiply by .
Take the square root of both sides of the equation to eliminate the exponent on the left side.
The complete solution is the result of both the positive and negative portions of the solution.
Simplify the right side of the equation.
Simplify the expression.
Rewrite as .
Reorder and .
Since both terms are perfect squares, factor using the difference of squares formula, where and .
The complete solution is the result of both the positive and negative portions of the solution.
First, use the positive value of the to find the first solution.
Next, use the negative value of the to find the second solution.
The complete solution is the result of both the positive and negative portions of the solution.
To rewrite as a function of , write the equation so that is by itself on one side of the equal sign and an expression involving only is on the other side.
Write as a Function of y y = square root of 49-x^2