Answer:
See below.
Step-by-step explanation:
Two
Up to the fourth line is correct. The fifth line contains the error.
Line four take the square root of both sides.
sqrt(x-3)^2 = sqrt(16)
x - 3 is correct = +/- 4
x - 3 = 4
x = 3 + 4
x = 7
x - 3 = - 4
x = -4 + 3
x = - 2
The two answers should be (7,0) and (-2,0)
Three
x^2 - 4x + 3 = 0
This equation factors without the use of the quadratic formula
(x - 3)(x - 1) are its two factors.
So the two points are (3,0)(1,0). However I will be obedient to what you were asked for
a = 1
b = -4
c = 3
x = [- b +/- sqrt(b^2 - 4ac)] / (2a)
x = [ -(-4) +/- sqrt(4^2 - 4(1)(3)]/(2*1)
x = [4 +/- sqrt(16 - 12) ] / 2
x = (4 +/- 2) / 2
x = 2 /2 = 1
or
x = 6/2 = 3
Question 4
(x - 4)^2 - 28 = 8 Add 28 to both sides
(x -4)^2 - 28 + 28 = 8 + 28 Combine like terms on the left and right
(x - 4)^2 = 36 Take the square root of both sides.
x - 4 = +/- 6
x - 4 = 6
x = 6 + 4
x = 10
========
x - 4 = - 6
x = -6 + 4
x = - 2
The two points which are solutions are
(10,0)(-2,0)