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1. open up = (x-2) * (x-2) = 25

x squared – 2x -2x +4 = 25

x squared -4x +4 =25

x squared -4x +4 -4 =25-4

x squared – 4x = 21

factor out x

x(x-4) =21

………..im stuck ……get someone to help you from there im sure im on the right track just that i dont remember if you get the log on both sides or something else……. 🙂

2. in the second question take 30x to the other side

5xsquared = -30x

divide both sides by x

5x squared/x = -30x/x

5x= -30

divide both sides by 5

5x/5 = -30/5

x = – 6 (negative 6)

3. 5x squared -20 = 0

take 20 on the other side

5x squared – 20 +20 = 0 +20

5x squared = 20

divide both sides by 5

5 x squared / 5 = 20/5

x squared = 4

get square root

x = 2 the other intercept is x= – 2

(negative x negative = positive) (-2 x -2 = +4)

Have fun with the math

so (x-2)(x-2) = 25

now, you need to work further:

(x-2)(x-2) = 25

x^2 – 4x + 4 = 25

x^2 – 4x = 25 – 4

x(x – 4) = 21

x = 7

2) 5x^2 + 30x = 0