Help with algebra 2 please
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Answer:
10
Step-by-step explanation:
sqrt(9x+10) = x
Square each side
(sqrt(9x+10))^2 = x^2
9x+10 = x^2
Subtract 9x from each side
9x-9x+10 = x^2-9x
10 = x^2 -9x
Subtract 10 from each side
10-10 = x^2 -9x -10
0 = x^2 -9x -10
Factor
0 = (x-10) (x+1)
x =10, x=-1
Since we squared each side we need to check for extraneous solutions
sqrt(9x+10) = x
Let x = -1
sqrt(9(-1)+10) = -1
sqrt(-9+10) = -1
sqrt(1) = -1
1 = -1
False
Extraneous solution
sqrt(9x+10) = x
Let x = 10
sqrt(9(10)+10) = 10
sqrt(90+10) = 10
sqrt(10) = 10
True