Can someone please solve this.
Oh and please either throughly explain and/or attach a photo so that I can understand your thinking.

PLEASE & THANK YOU

see explanation

Step-by-step explanation:

A

Given

(x² + 3)² + 21 = 10x² + 30 ← factor out 10 from each term on the right side

(x² + 3)² + 21 = 10(x² + 3) ← subtract 10(x² + 3) from both sides

(x² + 3)² - 10(x² + 3) + 21 = 0

Substituting u = x² + 3 into the equation gives

u² - 10u + 21 = 0 → D

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B

Using u² - 10u + 21 = 0 to solve the equation

Consider the factors of the constant term (+ 21) which sum to give the coefficient of the u- term (- 10)

The factors are - 3 and - 7, since

- 3 × - 7 = 21 and - 3 - 7 = - 10, thus

(u - 3)(u - 7) = 0

Equate each factor to zero and solve for u

u - 3 = 0 ⇒ u = 3

u - 7 = 0 ⇒ u = 7

We now have to use the substitution to convert the solutions into terms of x, that is

x² + 3 = 3 ( subtract 3 from both sides )

x² = 0 ⇒ x = 0 → D

x² + 3 = 7 ( subtract 3 from both sides )

x² = 4 ( take the square root of both sides )

x = ± = ± 2

Thus x = - 2 → C

x = 2 → E

i can answer this question sweetie!

step-by-step explanation:

to plot points   for x just start at the origin (middle) and go to the left however many times it say(if the number is a positive) if the number is a negative then go right however many times it says if it is 0 go nowhere

now keep you pencil there and go up however many times it says on y(if it is positive) if it is negative then go down however many times it says. if it says 0 go nowhere.

you have just plotted a point! now when you finish plotting all of them connect them with a ruler

plot each point as (-3, 7), (0,4), (3,1), (8,-4)   in the parenthesis on the left of the comma is x and the right is y.