Question

CAN ANYONE HELP PLEASE??

Answer 1

Answer:

Step-by-step explanation:

First Question

The top question has 2 solutions because eventually you will have to take the square root of (x - 4)^2. One square root will be plus, and the other minus

(x - 4)^2 - 28 = 8                 Add 28 to both sides

(x - 4)^2 -28+28 = 8+28     Collect like terms

(x - 4)^2 = 36                       Take the square root.

sqrt( (x - 4)^2 ) = sqrt(36)    

x - 4 = +/- 6

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x - 4 = + 6      

x = 6 + 4

x = 10

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x - 4 = - 6

x = - 6 + 4

x = - 2

The two solutions are (10,0) and (-2,0)

Second Question

The question is solved correctly up to the point where the square root needs to be taken. It is incorrect at that point.

x^2 - 6x - 7 = 0                             Add 7 to both sides.

x^2 - 6x  = 7                                  Add 1/2 the linear term and square it to both sides.

x^2 - 6x + (6/2)^2 = 7 + (6/2)^2    Expand the right

x^2 - 6x + 3^2 = 7 + 9                    

x^2 - 6x + 9 = 16                            express the square on the left

(x - 3)^2 = 16                                   Take the sqrt of both sides.

x - 3 = sqrt(16)

x - 3 = +/-4

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x - 3 = 4

x = 4 + 3

x = 7

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x -3 = - 4

x = - 4 + 3

x = - 1

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Solutions

(7,0) and (-1,0)