square root(-9x-2)=8x+9?

Question

Need Solutions and work

Answer 1

Square both sides to get rid of square root:

-9x - 2 = (8x + 9)^2

FOIL right hand side

-9x - 2 = 64x^2 + 144x + 81

simplify (collect like terms)

0 = 64x^2 +153x + 83

now solve this by using quadratic formula (or maybe it factors nicely; I don't see that off of the top of my head)

warning: you will get two answers, but one of them might not work because of squaring both sides initially. you need to plug both back into the original equation and check to make sure they work. if one doesn't work, discard it.

Answer 2

sq rt(-9x - 2) = 8x + 9
First remove the sq.rt. by squaring the whole equation
(-9x - 2 ) = (8x + 9)^2
-9x - 2 = (8x + 9)(8x + 9)
-9x - 2 = 64x^2 + 72x + 72x + 81
-9x - 2 = 64x^2 + 144x + 81
64x^2 + 144x + 9x + 81 + 2=0
64x^2 + 153x + 83 = 0
Using 'Completing the Square' equation:-
x = {- 153 +/- sqrt[ 152^2 - 4(64)(83)]}/2(64)
x = {-153 +/- sqrt[23104 - 21248]}/128
x = { -153 +/- sqrt{1856}}/128
x = {-153 +/- 43.08131846}/128
x = {-153 + 43.08131846}/128
First answer for 'x'
x = -109.9186815/128 = -0.858739699 ( -0.86 2dp)
Second answer for 'x'
x = -196.0813185/128 = -1.5318853 (-1.53 2dp)

Answer 3

√(-9x-2) = 8x+9,
Domain: -9/8 ≤ x ≤ -2/9
Square both sides,
-9x-2 = 64x^2+144x+81
64x^+153x+83 = 0
x = -0.8321 is the only solution, since x = -1.558 is not in the domain.
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Ideas: Find the domain first.

Answer 4

sqrt( -9x - 2) = 8x + 9
-9x - 2 = (8x + 9)^2
-9x - 2 = 64x^2 + 144x + 81
64x^2 + 153x + 83 = 0
x = [ -153 +or- sqrt(153^2 -4(64)83 ) ] / 128
[ -153 +or- sqrt(2161) ]/ 128

Answer 5

=
-9x - 2 = (8x + 9)^2
-9x - 2 = 64x^2 + (2 * 8x * 9) + 81
-9x - 2 = 64x^2 + 144x + 81
0 = 64x^2 + 153x + 83

(153+or- (153^2 - (4*64*83))^(1/2)) / (2*64)
(153 + or - (2161)^(1/2) ) / 128
x = 1.558 or 0.832

Answer 6

are u asking the square root of (-9x-2) ? is the expression on the L.H.S your answer? or is it the square root of the whole expression u are asking for. pls put the question properly.