Pearson Algebra 1 Common Core, 2011
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Pearson Algebra 1 Common Core, 2011 View details
4. Solving Radical Equations
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Exercise 42 Page 637

Begin with x=3 and modify this equation by doing the same operation to each side of the equation.

Example Equations: sqrt(x+6)=3 and 2sqrt(m-3)=0

Practice makes perfect

We are asked to write two radical equations that have 3 for a solution. First, let's recall that a radical equation is an equation that has a variable in a radicand. We will deal with one equation at a time. Keep in mind that there infinitely many radical equations that have a solution of 3, so answers may vary.

First Equation

Since we are told that 3 should be the solution of our equation, we can start with the solution equation. x=3 Now, let's modify it by doing different operations to both sides of the equation. For example, we can add 6 to both sides using the Addition Property of Equality. x+ 6=3+ 6 ⇔ x+6=9 Next, because we want to end up with a radical equation, let's calculate the square root of each side. sqrt(x+6)=sqrt(9) ⇔ sqrt(x+6)=3 We conclude that radical equation sqrt(x+6)=3 has 3 for a solution. To make sure, let's substitute 3 for x and see is the equation is true.
sqrt(x+6)=3
sqrt(3+6)? =3
sqrt(9)? =3
3=3 âś“

Second Equation

We can form the second radical equation in a similar way. This time we can choose another variable and set it equal to 3. m=3 Next, let's subtract 3 from each side of the equation using the Subtraction Property of Equality. m- 3=3- 3 ⇔ m-3=0 We can also take a cube root of each side. sqrt(m-3)=sqrt(0) ⇔ sqrt(m-3)=0 Finally, we will multiply the sides of the equation by 2 using the Multiplication Property of Equality. 2sqrt(m-3)= 2* 0 ⇔ 2sqrt(m-3)=0 Again, we can check our equation by substituting 3 for m into the equation.
2sqrt(m-3)=0
2sqrt(3-3)? =0
2sqrt(0)? =0
2* 0? =0
0=0 âś“