7.5 Solving Radical Equations
What is a Radical Expression? yes A Radical Expression is an equation that has a variable in a radicand or has a variable with a rational exponent. yes no
EXAMPLE – Solving a Radical Equation 2 2 Square both sides to get rid of the square root ( )
EXAMPLE ( ) 2 2 NO SOLUTION Since 16 doesn’t plug in as a solution. Note: You will get Extraneous Solutions from time to time – always do a quick check Let’s Double Check that this works
Let’s Try Some
Let’s Try Some
RADICAL EQUATIONS ISOLATE RADICAL / RATIONAL RAISE BOTH SIDES TO RECIPROCAL POWER SOLVE FOR THE VARIABLE
Can graphing calculators help? SURE! Input for Y1 Input x-2 for Y2 Graph Find the points of intersection One Solution at (4, 2) To see if this is extraneous or not, plug the x value back into the equation. Does it work?