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Find the non-extraneous solutions of the square root of the quantity of x plus 3 minus 4 equals x minus 1.

2 Answers

3 votes
x+3=(x+3)^2
x+3=(x+3)(x+3)
x+3= x^2+6x+9
x=x^2+6x+6
0=x^2+5x+6
0=(x+3)(x+2)
x=-2
x=-3
User Geogeek
by
8.3k points
1 vote

Answer:

x=-2 and x=-3

Explanation:


√(x+3) -4= x-1

Solve the equation for x

Add 4 on both sides


√(x+3)= x+3

Now take square on both sides


x+3= (x+3)^2


x+3= (x+3)(x+3)


x+3= x^2+6x+9


x=x^2+6x+6


0=x^2+5x+6


0=(x+3)(x+2)

x+3=0, x=-3

x+2=0, x=-2

LEts plug in -2 for x and verify the solution


√(x+3) -4= x-1


√(-2+3) -4= -2-1


√(1) -4=-3


-3=-3 True

Plug in x=-3


√(-3+3) -4= -3-1


√(0) -4=-4


-4=-4 True

So x=-2 and x=-3 are the non extraneous solution

User NZD
by
8.5k points